,,
,
,
- ,
etc,
// each time we enter one of those spans must ++ the indentation level void _Wikitext_indent(parser_t *parser) { int space_count = parser->current_indent + parser->base_indent; if (space_count > 0) { char *old_end, *new_end; if (parser->tabulation->len < space_count) str_grow(parser->tabulation, space_count); // reallocates if necessary old_end = parser->tabulation->ptr + parser->tabulation->len; new_end = parser->tabulation->ptr + space_count; while (old_end < new_end) *old_end++ = ' '; if (space_count > parser->tabulation->len) parser->tabulation->len = space_count; rb_str_cat(parser->output, parser->tabulation->ptr, space_count); } parser->current_indent += 2; } void _Wikitext_dedent(parser_t *parser, VALUE emit) { parser->current_indent -= 2; if (emit != Qtrue) return; int space_count = parser->current_indent + parser->base_indent; if (space_count > 0) rb_str_cat(parser->output, parser->tabulation->ptr, space_count); } // Pops a single item off the parser's scope stack. // A corresponding closing tag is written to the target string. // The target string may be the main output buffer, or a substring capturing buffer if a link is being scanned. void _Wikitext_pop_from_stack(parser_t *parser, VALUE target) { int top = ary_entry(parser->scope, -1); if (NO_ITEM(top)) return; if (NIL_P(target)) target = parser->output; switch (top) { case PRE: case PRE_START: rb_str_cat(target, pre_end, sizeof(pre_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case BLOCKQUOTE: case BLOCKQUOTE_START: _Wikitext_dedent(parser, Qtrue); rb_str_cat(target, blockquote_end, sizeof(blockquote_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); break; case NO_WIKI_START: // not a real HTML tag; so nothing to pop break; case STRONG: case STRONG_START: rb_str_cat(target, strong_end, sizeof(strong_end) - 1); break; case EM: case EM_START: rb_str_cat(target, em_end, sizeof(em_end) - 1); break; case TT: case TT_START: rb_str_cat(target, tt_end, sizeof(tt_end) - 1); break; case OL: _Wikitext_dedent(parser, Qtrue); rb_str_cat(target, ol_end, sizeof(ol_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); break; case UL: _Wikitext_dedent(parser, Qtrue); rb_str_cat(target, ul_end, sizeof(ul_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); break; case NESTED_LIST: // next token to pop will be a LI // LI is an interesting token because sometimes we want it to behave like P (ie. do a non-emitting indent) // and other times we want it to behave like BLOCKQUOTE (ie. when it has a nested list inside) // hence this hack: we do an emitting dedent on behalf of the LI that we know must be coming // and then when we pop the actual LI itself (below) we do the standard non-emitting indent _Wikitext_dedent(parser, Qtrue); // we really only want to emit the spaces parser->current_indent += 2; // we don't want to decrement the actual indent level, so put it back break; case LI: rb_str_cat(target, li_end, sizeof(li_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case H6_START: rb_str_cat(target, h6_end, sizeof(h6_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case H5_START: rb_str_cat(target, h5_end, sizeof(h5_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case H4_START: rb_str_cat(target, h4_end, sizeof(h4_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case H3_START: rb_str_cat(target, h3_end, sizeof(h3_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case H2_START: rb_str_cat(target, h2_end, sizeof(h2_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case H1_START: rb_str_cat(target, h1_end, sizeof(h1_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case LINK_START: // not an HTML tag; so nothing to emit break; case EXT_LINK_START: // not an HTML tag; so nothing to emit break; case SPACE: // not an HTML tag (only used to separate an external link target from the link text); so nothing to emit break; case SEPARATOR: // not an HTML tag (only used to separate an external link target from the link text); so nothing to emit break; case P: rb_str_cat(target, p_end, sizeof(p_end) - 1); rb_str_cat(target, parser->line_ending->ptr, parser->line_ending->len); _Wikitext_dedent(parser, Qfalse); break; case END_OF_FILE: // nothing to do break; default: // should probably raise an exception here break; } ary_pop(parser->scope); } // Pops items off the top of parser's scope stack, accumulating closing tags for them into the target string, until item is reached. // If including is Qtrue then the item itself is also popped. // The target string may be the main output buffer, or a substring capturing buffer when scanning links. void _Wikitext_pop_from_stack_up_to(parser_t *parser, VALUE target, int item, VALUE including) { int continue_looping = 1; do { int top = ary_entry(parser->scope, -1); if (NO_ITEM(top)) return; if (top == item) { if (including != Qtrue) return; continue_looping = 0; } _Wikitext_pop_from_stack(parser, target); } while (continue_looping); } void _Wikitext_start_para_if_necessary(parser_t *parser) { if (!NIL_P(parser->capture)) // we don't do anything if in capturing mode return; // if no block open yet, or top of stack is BLOCKQUOTE/BLOCKQUOTE_START (with nothing in it yet) if (parser->scope->count == 0 || ary_entry(parser->scope, -1) == BLOCKQUOTE || ary_entry(parser->scope, -1) == BLOCKQUOTE_START) { _Wikitext_indent(parser); rb_str_cat(parser->output, p_start, sizeof(p_start) - 1); ary_push(parser->scope, P); ary_push(parser->line, P); } else if (parser->pending_crlf == Qtrue) { if (IN(P)) // already in a paragraph block; convert pending CRLF into a space rb_str_cat(parser->output, space, sizeof(space) - 1); else if (IN(PRE)) // PRE blocks can have pending CRLF too (helps us avoid emitting the trailing newline) rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); } parser->pending_crlf = Qfalse; } void _Wikitext_emit_pending_crlf_if_necessary(parser_t *parser) { if (parser->pending_crlf == Qtrue) { rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); parser->pending_crlf = Qfalse; } } // Helper function that pops any excess elements off scope (pushing is already handled in the respective rules). // For example, given input like: // // > > foo // bar // // Upon seeing "bar", we want to pop two BLOCKQUOTE elements from the scope. // The reverse case (shown below) is handled from inside the BLOCKQUOTE rule itself: // // foo // > > bar // // Things are made slightly more complicated by the fact that there is one block-level tag that can be on the scope // but not on the line scope: // //foo // bar// // Here on seeing "bar" we have one item on the scope (BLOCKQUOTE_START) which we don't want to pop, but we have nothing // on the line scope. // Luckily, BLOCKQUOTE_START tokens can only appear at the start of the scope array, so we can check for them first before // entering the for loop. void _Wikitext_pop_excess_elements(parser_t *parser) { if (!NIL_P(parser->capture)) // we don't pop anything if in capturing mode return; for (int i = parser->scope->count - ary_count(parser->scope, BLOCKQUOTE_START), j = parser->line->count; i > j; i--) { // special case for last item on scope if (i - j == 1) { // don't auto-pop P if it is only item on scope if (ary_entry(parser->scope, -1) == P) { // add P to the line scope to prevent us entering the loop at all next time around ary_push(parser->line, P); continue; } } _Wikitext_pop_from_stack(parser, parser->output); } } #define INVALID_ENCODING(msg) do { if (dest_ptr) free(dest_ptr); rb_raise(eWikitextParserError, "invalid encoding: " msg); } while(0) // convert a single UTF-8 codepoint to UTF-32 // expects an input buffer, src, containing a UTF-8 encoded character (which may be multi-byte) // the end of the input buffer, end, is also passed in to allow the detection of invalidly truncated codepoints // the number of bytes in the UTF-8 character (between 1 and 4) is returned by reference in width_out // raises a RangeError if the supplied character is invalid UTF-8 // (in which case it also frees the block of memory indicated by dest_ptr if it is non-NULL) uint32_t _Wikitext_utf8_to_utf32(char *src, char *end, long *width_out, void *dest_ptr) { uint32_t dest; if ((unsigned char)src[0] <= 0x7f) // ASCII { dest = src[0]; *width_out = 1; } else if ((src[0] & 0xe0) == 0xc0) // byte starts with 110..... : this should be a two-byte sequence { if (src + 1 >= end) INVALID_ENCODING("truncated byte sequence"); // no second byte else if (((unsigned char)src[0] == 0xc0) || ((unsigned char)src[0] == 0xc1)) INVALID_ENCODING("overlong encoding"); // overlong encoding: lead byte of 110..... but code point <= 127 else if ((src[1] & 0xc0) != 0x80 ) INVALID_ENCODING("malformed byte sequence"); // should have second byte starting with 10...... dest = ((uint32_t)(src[0] & 0x1f)) << 6 | (src[1] & 0x3f); *width_out = 2; } else if ((src[0] & 0xf0) == 0xe0) // byte starts with 1110.... : this should be a three-byte sequence { if (src + 2 >= end) INVALID_ENCODING("truncated byte sequence"); // missing second or third byte else if (((src[1] & 0xc0) != 0x80 ) || ((src[2] & 0xc0) != 0x80 )) INVALID_ENCODING("malformed byte sequence"); // should have second and third bytes starting with 10...... dest = ((uint32_t)(src[0] & 0x0f)) << 12 | ((uint32_t)(src[1] & 0x3f)) << 6 | (src[2] & 0x3f); *width_out = 3; } else if ((src[0] & 0xf8) == 0xf0) // bytes starts with 11110... : this should be a four-byte sequence { if (src + 3 >= end) INVALID_ENCODING("truncated byte sequence"); // missing second, third, or fourth byte else if ((unsigned char)src[0] >= 0xf5 && (unsigned char)src[0] <= 0xf7) INVALID_ENCODING("overlong encoding"); // disallowed by RFC 3629 (codepoints above 0x10ffff) else if (((src[1] & 0xc0) != 0x80 ) || ((src[2] & 0xc0) != 0x80 ) || ((src[3] & 0xc0) != 0x80 )) INVALID_ENCODING("malformed byte sequence"); // should have second and third bytes starting with 10...... dest = ((uint32_t)(src[0] & 0x07)) << 18 | ((uint32_t)(src[1] & 0x3f)) << 12 | ((uint32_t)(src[1] & 0x3f)) << 6 | (src[2] & 0x3f); *width_out = 4; } else // invalid input INVALID_ENCODING("unexpected byte"); return dest; } VALUE _Wikitext_utf32_char_to_entity(uint32_t character) { // TODO: consider special casing some entities (ie. quot, amp, lt, gt etc)? char hex_string[8] = { '&', '#', 'x', 0, 0, 0, 0, ';' }; char scratch = (character & 0xf000) >> 12; hex_string[3] = (scratch <= 9 ? scratch + 48 : scratch + 87); scratch = (character & 0x0f00) >> 8; hex_string[4] = (scratch <= 9 ? scratch + 48 : scratch + 87); scratch = (character & 0x00f0) >> 4; hex_string[5] = (scratch <= 9 ? scratch + 48 : scratch + 87); scratch = character & 0x000f; hex_string[6] = (scratch <= 9 ? scratch + 48 : scratch + 87); return rb_str_new((const char *)hex_string, sizeof(hex_string)); } VALUE _Wikitext_parser_trim_link_target(VALUE string) { string = StringValue(string); char *src = RSTRING_PTR(string); char *start = src; // remember this so we can check if we're at the start char *left = src; char *non_space = src; // remember last non-space character output long len = RSTRING_LEN(string); char *end = src + len; while (src < end) { if (*src == ' ') { if (src == left) left++; } else non_space = src; src++; } if (left == start && non_space + 1 == end) return string; else return rb_str_new(left, (non_space + 1) - left); } // - non-printable (non-ASCII) characters converted to numeric entities // - QUOT and AMP characters converted to named entities // - if rollback is Qtrue, there is no special treatment of spaces // - if rollback is Qfalse, leading and trailing whitespace trimmed if trimmed VALUE _Wikitext_parser_sanitize_link_target(parser_t *parser, VALUE rollback) { VALUE string = StringValue(parser->link_target); // raises if string is nil or doesn't quack like a string char *src = RSTRING_PTR(string); char *start = src; // remember this so we can check if we're at the start long len = RSTRING_LEN(string); char *end = src + len; // start with a destination buffer twice the size of the source, will realloc if necessary // slop = (len / 8) * 8 (ie. one in every 8 characters can be converted into an entity, each entity requires 8 bytes) // this efficiently handles the most common case (where the size of the buffer doesn't change much) char *dest = ALLOC_N(char, len * 2); char *dest_ptr = dest; // hang on to this so we can pass it to free() later char *non_space = dest; // remember last non-space character output while (src < end) { // need at most 8 characters (8 bytes) to display each character if (dest + 8 > dest_ptr + len) // outgrowing buffer, must reallocate { char *old_dest = dest; char *old_dest_ptr = dest_ptr; len = len + (end - src) * 8; // allocate enough for worst case dest = realloc(dest_ptr, len); // will never have to realloc more than once if (dest == NULL) { // would have used reallocf, but this has to run on Linux too, not just Darwin free(dest_ptr); rb_raise(rb_eNoMemError, "failed to re-allocate temporary storage (memory allocation error)"); } dest_ptr = dest; dest = dest_ptr + (old_dest - old_dest_ptr); non_space = dest_ptr + (non_space - old_dest_ptr); } if (*src == '"') // QUOT { char quot_entity_literal[] = { '&', 'q', 'u', 'o', 't', ';' }; // no trailing NUL memcpy(dest, quot_entity_literal, sizeof(quot_entity_literal)); dest += sizeof(quot_entity_literal); } else if (*src == '&') // AMP { char amp_entity_literal[] = { '&', 'a', 'm', 'p', ';' }; // no trailing NUL memcpy(dest, amp_entity_literal, sizeof(amp_entity_literal)); dest += sizeof(amp_entity_literal); } else if (*src == '<') // LESS_THAN { free(dest_ptr); rb_raise(rb_eRangeError, "invalid link text (\"<\" may not appear in link text)"); } else if (*src == '>') // GREATER_THAN { free(dest_ptr); rb_raise(rb_eRangeError, "invalid link text (\">\" may not appear in link text)"); } else if (*src == ' ' && src == start && rollback == Qfalse) start++; // we eat leading space else if (*src >= 0x20 && *src <= 0x7e) // printable ASCII { *dest = *src; dest++; } else // all others: must convert to entities { long width; VALUE entity = _Wikitext_utf32_char_to_entity(_Wikitext_utf8_to_utf32(src, end, &width, dest_ptr)); char *entity_src = RSTRING_PTR(entity); long entity_len = RSTRING_LEN(entity); // should always be 8 characters (8 bytes) memcpy(dest, entity_src, entity_len); dest += entity_len; src += width; non_space = dest; continue; } if (*src != ' ') non_space = dest; src++; } // trim trailing space if necessary if (rollback == Qfalse && non_space > dest_ptr && dest != non_space) len = non_space - dest_ptr; else len = dest - dest_ptr; VALUE out = rb_str_new(dest_ptr, len); free(dest_ptr); return out; } VALUE Wikitext_parser_sanitize_link_target(VALUE self, VALUE string) { parser_t parser; parser.link_target = string; return _Wikitext_parser_sanitize_link_target(&parser, Qfalse); } // encodes the input string according to RFCs 2396 and 2718 // leading and trailing whitespace trimmed // note that the first character of the target link is not case-sensitive // (this is a recommended application-level constraint; it is not imposed at this level) // this is to allow links like: // ...the [[foo]] is... // to be equivalent to: // thing. [[Foo]] was... // this is also where we check treat_slash_as_special is true and act accordingly // basically any link target matching /\A[a-z]+\/\d+\z/ is flagged as special static void _Wikitext_parser_encode_link_target(parser_t *parser) { VALUE in = StringValue(parser->link_target); char *input = RSTRING_PTR(in); char *start = input; // remember this so we can check if we're at the start long len = RSTRING_LEN(in); if (!(len > 0)) return; char *end = input + len; static char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; // this potential shortcut requires an (admittedly cheap) prescan, so only do it when treat_slash_as_special is true parser->special_link = Qfalse; if (parser->treat_slash_as_special == Qtrue) { char *c = input; // \A while (c < end && *c >= 'a' && *c <= 'z') // [a-z] c++; // + if (c > start && c < end && *c++ == '/') // \/ { while (c < end && *c >= '0' && *c <= '9') // \d { c++; // + if (c == end) // \z { // matches /\A[a-z]+\/\d+\z/ so no transformation required parser->special_link = Qtrue; return; } } } } // to avoid most reallocations start with a destination buffer twice the size of the source // this handles the most common case (where most chars are in the ASCII range and don't require more storage, but there are // often quite a few spaces, which are encoded as "%20" and occupy 3 bytes) // the worst case is where _every_ byte must be written out using 3 bytes long dest_len = len * 2; char *dest = ALLOC_N(char, dest_len); char *dest_ptr = dest; // hang on to this so we can pass it to free() later char *non_space = dest; // remember last non-space character output for (; input < end; input++) { if ((dest + 3) > (dest_ptr + dest_len)) // worst case: a single character may grow to 3 characters once encoded { // outgrowing buffer, must reallocate char *old_dest = dest; char *old_dest_ptr = dest_ptr; dest_len += len; dest = realloc(dest_ptr, dest_len); if (dest == NULL) { // would have used reallocf, but this has to run on Linux too, not just Darwin free(dest_ptr); rb_raise(rb_eNoMemError, "failed to re-allocate temporary storage (memory allocation error)"); } dest_ptr = dest; dest = dest_ptr + (old_dest - old_dest_ptr); non_space = dest_ptr + (non_space - old_dest_ptr); } // pass through unreserved characters if (((*input >= 'a') && (*input <= 'z')) || ((*input >= 'A') && (*input <= 'Z')) || ((*input >= '0') && (*input <= '9')) || (*input == '-') || (*input == '_') || (*input == '.') || (*input == '~')) { *dest++ = *input; non_space = dest; } else if (*input == ' ' && input == start) start++; // we eat leading space else if (*input == ' ' && parser->space_to_underscore == Qtrue) *dest++ = '_'; else // everything else gets URL-encoded { *dest++ = '%'; *dest++ = hex[(unsigned char)(*input) / 16]; // left *dest++ = hex[(unsigned char)(*input) % 16]; // right if (*input != ' ') non_space = dest; } } // trim trailing space if necessary if (non_space > dest_ptr && dest != non_space) dest_len = non_space - dest_ptr; else dest_len = dest - dest_ptr; parser->link_target = rb_str_new(dest_ptr, dest_len); free(dest_ptr); } VALUE Wikitext_parser_encode_link_target(VALUE self, VALUE in) { parser_t parser; parser.link_target = in; parser.treat_slash_as_special = Qfalse; parser.space_to_underscore = Qfalse; _Wikitext_parser_encode_link_target(&parser); return parser.link_target; } // this method exposed for testing only VALUE Wikitext_parser_encode_special_link_target(VALUE self, VALUE in) { parser_t parser; parser.link_target = in; parser.treat_slash_as_special = Qtrue; parser.space_to_underscore = Qfalse; _Wikitext_parser_encode_link_target(&parser); return parser.link_target; } void _Wikitext_rollback_failed_link(parser_t *parser) { if (!IN(LINK_START)) return; // nothing to do! int scope_includes_separator = IN(SEPARATOR); _Wikitext_pop_from_stack_up_to(parser, Qnil, LINK_START, Qtrue); rb_str_cat(parser->output, link_start, sizeof(link_start) - 1); if (!NIL_P(parser->link_target)) { VALUE sanitized = _Wikitext_parser_sanitize_link_target(parser, Qtrue); rb_str_append(parser->output, sanitized); if (scope_includes_separator) { rb_str_cat(parser->output, separator, sizeof(separator) - 1); if (!NIL_P(parser->link_text)) rb_str_append(parser->output, parser->link_text); } } parser->capture = Qnil; parser->link_target = Qnil; parser->link_text = Qnil; } void _Wikitext_rollback_failed_external_link(parser_t *parser) { if (!IN(EXT_LINK_START)) return; // nothing to do! int scope_includes_space = IN(SPACE); _Wikitext_pop_from_stack_up_to(parser, Qnil, EXT_LINK_START, Qtrue); rb_str_cat(parser->output, ext_link_start, sizeof(ext_link_start) - 1); if (!NIL_P(parser->link_target)) { if (parser->autolink == Qtrue) parser->link_target = _Wikitext_hyperlink(Qnil, parser->link_target, parser->link_target, parser->external_link_class); rb_str_append(parser->output, parser->link_target); if (scope_includes_space) { rb_str_cat(parser->output, space, sizeof(space) - 1); if (!NIL_P(parser->link_text)) rb_str_append(parser->output, parser->link_text); } } parser->capture = Qnil; parser->link_target = Qnil; parser->link_text = Qnil; } VALUE Wikitext_parser_initialize(int argc, VALUE *argv, VALUE self) { // process arguments VALUE options; if (rb_scan_args(argc, argv, "01", &options) == 0) // 0 mandatory arguments, 1 optional argument options = Qnil; // defaults VALUE autolink = Qtrue; VALUE line_ending = rb_str_new2("\n"); VALUE external_link_class = rb_str_new2("external"); VALUE mailto_class = rb_str_new2("mailto"); VALUE internal_link_prefix = rb_str_new2("/wiki/"); VALUE img_prefix = rb_str_new2("/images/"); VALUE space_to_underscore = Qfalse; VALUE treat_slash_as_special = Qtrue; // process options hash (override defaults) if (!NIL_P(options) && TYPE(options) == T_HASH) { #define OVERRIDE_IF_SET(name) rb_funcall(options, rb_intern("has_key?"), 1, ID2SYM(rb_intern(#name))) == Qtrue ? \ rb_hash_aref(options, ID2SYM(rb_intern(#name))) : name autolink = OVERRIDE_IF_SET(autolink); line_ending = OVERRIDE_IF_SET(line_ending); external_link_class = OVERRIDE_IF_SET(external_link_class); mailto_class = OVERRIDE_IF_SET(mailto_class); internal_link_prefix = OVERRIDE_IF_SET(internal_link_prefix); img_prefix = OVERRIDE_IF_SET(img_prefix); space_to_underscore = OVERRIDE_IF_SET(space_to_underscore); treat_slash_as_special = OVERRIDE_IF_SET(treat_slash_as_special); } // no need to call super here; rb_call_super() rb_iv_set(self, "@autolink", autolink); rb_iv_set(self, "@line_ending", line_ending); rb_iv_set(self, "@external_link_class", external_link_class); rb_iv_set(self, "@mailto_class", mailto_class); rb_iv_set(self, "@internal_link_prefix", internal_link_prefix); rb_iv_set(self, "@img_prefix", img_prefix); rb_iv_set(self, "@space_to_underscore", space_to_underscore); rb_iv_set(self, "@treat_slash_as_special", treat_slash_as_special); return self; } VALUE Wikitext_parser_profiling_parse(VALUE self, VALUE string) { for (int i = 0; i < 100000; i++) Wikitext_parser_parse(1, &string, self); return Qnil; } VALUE Wikitext_parser_parse(int argc, VALUE *argv, VALUE self) { // process arguments VALUE string, options; if (rb_scan_args(argc, argv, "11", &string, &options) == 1) // 1 mandatory argument, 1 optional argument options = Qnil; if (NIL_P(string)) return Qnil; string = StringValue(string); // process options hash int base_indent = 0; VALUE indent = Qnil; if (!NIL_P(options) && TYPE(options) == T_HASH) { indent = rb_hash_aref(options, ID2SYM(rb_intern("indent"))); base_indent = NUM2INT(indent); if (base_indent < 0) base_indent = 0; } // set up scanner char *p = RSTRING_PTR(string); long len = RSTRING_LEN(string); char *pe = p + len; // access these once per parse VALUE line_ending = rb_iv_get(self, "@line_ending"); line_ending = StringValue(line_ending); VALUE link_class = rb_iv_get(self, "@external_link_class"); link_class = NIL_P(link_class) ? Qnil : StringValue(link_class); VALUE mailto_class = rb_iv_get(self, "@mailto_class"); mailto_class = NIL_P(mailto_class) ? Qnil : StringValue(mailto_class); VALUE prefix = rb_iv_get(self, "@internal_link_prefix"); // set up parser struct to make passing parameters a little easier // eventually this will encapsulate most or all of the variables above parser_t _parser; parser_t *parser = &_parser; parser->output = rb_str_new2(""); parser->capture = Qnil; parser->link_target = Qnil; parser->link_text = Qnil; parser->external_link_class = link_class; parser->img_prefix = rb_iv_get(self, "@img_prefix"); parser->scope = ary_new(); GC_WRAP_ARY(parser->scope, scope_gc); parser->line = ary_new(); GC_WRAP_ARY(parser->line, line_gc); parser->line_buffer = ary_new(); GC_WRAP_ARY(parser->line_buffer, line_buffer_gc); parser->pending_crlf = Qfalse; parser->autolink = rb_iv_get(self, "@autolink"); parser->treat_slash_as_special = rb_iv_get(self, "@treat_slash_as_special"); parser->space_to_underscore = rb_iv_get(self, "@space_to_underscore"); parser->special_link = Qfalse; parser->line_ending = str_new_from_string(line_ending); GC_WRAP_STR(parser->line_ending, line_ending_gc); parser->base_indent = base_indent; parser->current_indent = 0; parser->tabulation = str_new(); GC_WRAP_STR(parser->tabulation, tabulation_gc); token_t _token; _token.type = NO_TOKEN; token_t *token = NULL; do { // note that whenever we grab a token we push it into the line buffer // this provides us with context-sensitive "memory" of what's been seen so far on this line #define NEXT_TOKEN() token = &_token, next_token(token, token, NULL, pe), ary_push(parser->line_buffer, token->type) // check to see if we have a token hanging around from a previous iteration of this loop if (token == NULL) { if (_token.type == NO_TOKEN) { // first time here (haven't started scanning yet) token = &_token; next_token(token, NULL, p, pe); ary_push(parser->line_buffer, token->type); } else // already scanning NEXT_TOKEN(); } int type = token->type; // can't declare new variables inside a switch statement, so predeclare them here long remove_strong = -1; long remove_em = -1; // general purpose counters and flags long i = 0; long j = 0; long k = 0; // The following giant switch statement contains cases for all the possible token types. // In the most basic sense we are emitting the HTML that corresponds to each token, // but some tokens require context information in order to decide what to output. // For example, does the STRONG token (''') translate to or ? // So when looking at any given token we have three state-maintaining variables which gives us a notion of "where we are": // // - the "scope" stack (indicates what HTML DOM structures we are currently nested inside, similar to a CSS selector) // - the line buffer (records tokens seen so far on the current line) // - the line "scope" stack (indicates what the scope should be based only on what is visible on the line so far) // // Although this is fairly complicated, there is one key simplifying factor: // The translator continuously performs auto-correction, and this means that we always have a guarantee that the // scope stack (up to the current token) is valid; our translator can take this as a given. // Auto-correction basically consists of inserting missing tokens (preventing subsquent HTML from being messed up), // or converting illegal (unexpected) tokens to their plain text equivalents (providing visual feedback to Wikitext author). switch (type) { case PRE: if (IN(NO_WIKI_START) || IN(PRE_START)) { rb_str_cat(parser->output, space, sizeof(space) - 1); break; } else if (IN(BLOCKQUOTE_START)) { // this kind of nesting not allowed (to avoid user confusion) _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); i = NIL_P(parser->capture) ? parser->output : parser->capture; rb_str_cat(i, space, sizeof(space) - 1); break; } // count number of BLOCKQUOTE tokens in line buffer and in scope stack ary_push(parser->line, PRE); i = ary_count(parser->line, BLOCKQUOTE); j = ary_count(parser->scope, BLOCKQUOTE); if (i < j) { // must pop (reduce nesting level) for (i = j - i; i > 0; i--) _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE, Qtrue); } if (!IN(PRE)) { parser->pending_crlf = Qfalse; _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE, Qfalse); _Wikitext_indent(parser); rb_str_cat(parser->output, pre_start, sizeof(pre_start) - 1); ary_push(parser->scope, PRE); } break; case PRE_START: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_pre_start, sizeof(escaped_pre_start) - 1); } else if (IN(BLOCKQUOTE_START)) { _Wikitext_rollback_failed_link(parser); // if any _Wikitext_rollback_failed_external_link(parser); // if any _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE_START, Qfalse); _Wikitext_indent(parser); rb_str_cat(parser->output, pre_start, sizeof(pre_start) - 1); ary_push(parser->scope, PRE_START); ary_push(parser->line, PRE_START); } else if (IN(BLOCKQUOTE)) { // PRE_START is illegal i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, escaped_pre_start, sizeof(escaped_pre_start) - 1); } else { _Wikitext_rollback_failed_link(parser); // if any _Wikitext_rollback_failed_external_link(parser); // if any _Wikitext_pop_from_stack_up_to(parser, Qnil, P, Qtrue); _Wikitext_indent(parser); rb_str_cat(parser->output, pre_start, sizeof(pre_start) - 1); ary_push(parser->scope, PRE_START); ary_push(parser->line, PRE_START); } break; case PRE_END: if (IN(NO_WIKI_START) || IN(PRE)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_pre_end, sizeof(escaped_pre_end) - 1); } else { if (IN(PRE_START)) _Wikitext_pop_from_stack_up_to(parser, parser->output, PRE_START, Qtrue); else { i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, escaped_pre_end, sizeof(escaped_pre_end) - 1); } } break; case BLOCKQUOTE: if (IN(NO_WIKI_START) || IN(PRE_START)) // no need to check for; can never appear inside it rb_str_cat(parser->output, escaped_blockquote, TOKEN_LEN(token) + 3); // will either emit ">" or "> " else if (IN(BLOCKQUOTE_START)) { // this kind of nesting not allowed (to avoid user confusion) _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); i = NIL_P(parser->capture) ? parser->output : parser->capture; rb_str_cat(i, escaped_blockquote, TOKEN_LEN(token) + 3); // will either emit ">" or "> " break; } else { ary_push(parser->line, BLOCKQUOTE); // count number of BLOCKQUOTE tokens in line buffer and in scope stack i = ary_count(parser->line, BLOCKQUOTE); j = ary_count(parser->scope, BLOCKQUOTE); // given that BLOCKQUOTE tokens can be nested, peek ahead and see if there are any more which might affect the decision to push or pop while (NEXT_TOKEN(), (token->type == BLOCKQUOTE)) { ary_push(parser->line, BLOCKQUOTE); i++; } // now decide whether to push, pop or do nothing if (i > j) { // must push (increase nesting level) _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE, Qfalse); for (i = i - j; i > 0; i--) { _Wikitext_indent(parser); rb_str_cat(parser->output, blockquote_start, sizeof(blockquote_start) - 1); rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); ary_push(parser->scope, BLOCKQUOTE); } } else if (i < j) { // must pop (reduce nesting level) for (i = j - i; i > 0; i--) _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE, Qtrue); } // jump to top of the loop to process token we scanned during lookahead continue; } break; case BLOCKQUOTE_START: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_blockquote_start, sizeof(escaped_blockquote_start) - 1); } else if (IN(BLOCKQUOTE_START)) { // nesting is fine here _Wikitext_rollback_failed_link(parser); // if any _Wikitext_rollback_failed_external_link(parser); // if any _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE_START, Qfalse); _Wikitext_indent(parser); rb_str_cat(parser->output, blockquote_start, sizeof(blockquote_start) - 1); rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); ary_push(parser->scope, BLOCKQUOTE_START); ary_push(parser->line, BLOCKQUOTE_START); } else if (IN(BLOCKQUOTE)) { // illegal here i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, escaped_blockquote_start, sizeof(escaped_blockquote_start) - 1); } else { // would be nice to eliminate the repetition here but it's probably the clearest way _Wikitext_rollback_failed_link(parser); // if any _Wikitext_rollback_failed_external_link(parser); // if any _Wikitext_pop_from_stack_up_to(parser, Qnil, P, Qtrue); _Wikitext_indent(parser); rb_str_cat(parser->output, blockquote_start, sizeof(blockquote_start) - 1); rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); ary_push(parser->scope, BLOCKQUOTE_START); ary_push(parser->line, BLOCKQUOTE_START); } break; case BLOCKQUOTE_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_blockquote_end, sizeof(escaped_blockquote_end) - 1); } else { if (IN(BLOCKQUOTE_START)) _Wikitext_pop_from_stack_up_to(parser, parser->output, BLOCKQUOTE_START, Qtrue); else { i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, escaped_blockquote_end, sizeof(escaped_blockquote_end) - 1); } } break; case NO_WIKI_START: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_no_wiki_start, sizeof(escaped_no_wiki_start) - 1); } else { _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); ary_push(parser->scope, NO_WIKI_START); ary_push(parser->line, NO_WIKI_START); } break; case NO_WIKI_END: if (IN(NO_WIKI_START)) //should always only ever be the last item in the stack, but use the helper routine just in case _Wikitext_pop_from_stack_up_to(parser, Qnil, NO_WIKI_START, Qtrue); else { _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, escaped_no_wiki_end, sizeof(escaped_no_wiki_end) - 1); } break; case STRONG_EM: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_strong_em, sizeof(literal_strong_em) - 1); break; } i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); // if you've seen STRONG/STRONG_START or EM/EM_START, must close them in the reverse order that you saw them! // otherwise, must open them remove_strong = -1; remove_em = -1; j = parser->scope->count; for (j = j - 1; j >= 0; j--) { int val = ary_entry(parser->scope, j); if (val == STRONG || val == STRONG_START) { rb_str_cat(i, strong_end, sizeof(strong_end) - 1); remove_strong = j; } else if (val == EM || val == EM_START) { rb_str_cat(i, em_end, sizeof(em_end) - 1); remove_em = j; } } if (remove_strong > remove_em) // must remove strong first { ary_pop(parser->scope); if (remove_em > -1) ary_pop(parser->scope); else // there was no em to remove!, so consider this an opening em tag { rb_str_cat(i, em_start, sizeof(em_start) - 1); ary_push(parser->scope, EM); ary_push(parser->line, EM); } } else if (remove_em > remove_strong) // must remove em first { ary_pop(parser->scope); if (remove_strong > -1) ary_pop(parser->scope); else // there was no strong to remove!, so consider this an opening strong tag { rb_str_cat(i, strong_start, sizeof(strong_start) - 1); ary_push(parser->scope, STRONG); ary_push(parser->line, STRONG); } } else // no strong or em to remove, so this must be a new opening of both { _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, strong_em_start, sizeof(strong_em_start) - 1); ary_push(parser->scope, STRONG); ary_push(parser->line, STRONG); ary_push(parser->scope, EM); ary_push(parser->line, EM); } break; case STRONG: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_strong, sizeof(literal_strong) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(STRONG_START)) // already in span started with , no choice but to emit this literally rb_str_cat(parser->output, literal_strong, sizeof(literal_strong) - 1); else if (IN(STRONG)) // STRONG already seen, this is a closing tag _Wikitext_pop_from_stack_up_to(parser, i, STRONG, Qtrue); else { // this is a new opening _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, strong_start, sizeof(strong_start) - 1); ary_push(parser->scope, STRONG); ary_push(parser->line, STRONG); } } break; case STRONG_START: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_strong_start, sizeof(escaped_strong_start) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(STRONG_START) || IN(STRONG)) rb_str_cat(parser->output, escaped_strong_start, sizeof(escaped_strong_start) - 1); else { _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, strong_start, sizeof(strong_start) - 1); ary_push(parser->scope, STRONG_START); ary_push(parser->line, STRONG_START); } } break; case STRONG_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_strong_end, sizeof(escaped_strong_end) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(STRONG_START)) _Wikitext_pop_from_stack_up_to(parser, i, STRONG_START, Qtrue); else { // no STRONG_START in scope, so must interpret the STRONG_END without any special meaning _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, escaped_strong_end, sizeof(escaped_strong_end) - 1); } } break; case EM: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_em, sizeof(literal_em) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(EM_START)) // already in span started with , no choice but to emit this literally rb_str_cat(parser->output, literal_em, sizeof(literal_em) - 1); else if (IN(EM)) // EM already seen, this is a closing tag _Wikitext_pop_from_stack_up_to(parser, i, EM, Qtrue); else { // this is a new opening _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, em_start, sizeof(em_start) - 1); ary_push(parser->scope, EM); ary_push(parser->line, EM); } } break; case EM_START: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_em_start, sizeof(escaped_em_start) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(EM_START) || IN(EM)) rb_str_cat(i, escaped_em_start, sizeof(escaped_em_start) - 1); else { _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, em_start, sizeof(em_start) - 1); ary_push(parser->scope, EM_START); ary_push(parser->line, EM_START); } } break; case EM_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_em_end, sizeof(escaped_em_end) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(EM_START)) _Wikitext_pop_from_stack_up_to(parser, i, EM_START, Qtrue); else { // no EM_START in scope, so must interpret the TT_END without any special meaning _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, escaped_em_end, sizeof(escaped_em_end) - 1); } } break; case TT: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, backtick, sizeof(backtick) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(TT_START)) // already in span started with , no choice but to emit this literally rb_str_cat(parser->output, backtick, sizeof(backtick) - 1); else if (IN(TT)) // TT (`) already seen, this is a closing tag _Wikitext_pop_from_stack_up_to(parser, i, TT, Qtrue); else { // this is a new opening _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, tt_start, sizeof(tt_start) - 1); ary_push(parser->scope, TT); ary_push(parser->line, TT); } } break; case TT_START: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_tt_start, sizeof(escaped_tt_start) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(TT_START) || IN(TT)) rb_str_cat(i, escaped_tt_start, sizeof(escaped_tt_start) - 1); else { _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, tt_start, sizeof(tt_start) - 1); ary_push(parser->scope, TT_START); ary_push(parser->line, TT_START); } } break; case TT_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, escaped_tt_end, sizeof(escaped_tt_end) - 1); } else { i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(TT_START)) _Wikitext_pop_from_stack_up_to(parser, i, TT_START, Qtrue); else { // no TT_START in scope, so must interpret the TT_END without any special meaning _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, escaped_tt_end, sizeof(escaped_tt_end) - 1); } } break; case OL: case UL: if (IN(NO_WIKI_START) || IN(PRE_START)) { // no need to check for PRE; can never appear inside it rb_str_cat(parser->output, token->start, TOKEN_LEN(token)); break; } // count number of tokens in line and scope stacks int bq_count = ary_count(parser->scope, BLOCKQUOTE_START); i = parser->line->count - ary_count(parser->line, BLOCKQUOTE_START); j = parser->scope->count - bq_count; k = i; // list tokens can be nested so look ahead for any more which might affect the decision to push or pop for (;;) { type = token->type; if (type == OL || type == UL) { token = NULL; if (i - k >= 2) // already seen at least one OL or UL { ary_push(parser->line, NESTED_LIST); // which means this is a nested list i += 3; } else i += 2; ary_push(parser->line, type); ary_push(parser->line, LI); // want to compare line with scope but can only do so if scope has enough items on it if (j >= i) { if (ary_entry(parser->scope, i + bq_count - 2) == type && ary_entry(parser->scope, i + bq_count - 1) == LI) { // line and scope match at this point: do nothing yet } else { // item just pushed onto line does not match corresponding slot of scope! for (; j >= i - 2; j--) // must pop back before emitting _Wikitext_pop_from_stack(parser, Qnil); // will emit UL or OL, then LI break; } } else // line stack size now exceeds scope stack size: must increase nesting level break; // will emit UL or OL, then LI } else { // not a OL or UL token! if (j == i) // must close existing LI and re-open new one _Wikitext_pop_from_stack(parser, Qnil); else if (j > i) { // item just pushed onto line does not match corresponding slot of scope! for (; j >= i; j--) // must pop back before emitting _Wikitext_pop_from_stack(parser, Qnil); } break; } NEXT_TOKEN(); } // will emit if (type == OL || type == UL) { // if LI is at the top of a stack this is the start of a nested list if (j > 0 && ary_entry(parser->scope, -1) == LI) { // so we should precede it with a CRLF, and indicate that it's a nested list rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); ary_push(parser->scope, NESTED_LIST); } else { // this is a new list if (IN(BLOCKQUOTE_START)) _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE_START, Qfalse); else _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE, Qfalse); } // emit _Wikitext_indent(parser); if (type == OL) rb_str_cat(parser->output, ol_start, sizeof(ol_start) - 1); else if (type == UL) rb_str_cat(parser->output, ul_start, sizeof(ul_start) - 1); ary_push(parser->scope, type); rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); } else if (type == SPACE) // silently throw away the optional SPACE token after final list marker token = NULL; _Wikitext_indent(parser); rb_str_cat(parser->output, li_start, sizeof(li_start) - 1); ary_push(parser->scope, LI); // any subsequent UL or OL tokens on this line are syntax errors and must be emitted literally if (type == OL || type == UL) { k = 0; while (k++, NEXT_TOKEN(), (type = token->type)) { if (type == OL || type == UL) rb_str_cat(parser->output, token->start, TOKEN_LEN(token)); else if (type == SPACE && k == 1) { // silently throw away the optional SPACE token after final list marker token = NULL; break; } else break; } } // jump to top of the loop to process token we scanned during lookahead continue; case H6_START: case H5_START: case H4_START: case H3_START: case H2_START: case H1_START: if (IN(NO_WIKI_START) || IN(PRE_START)) { // no need to check for PRE; can never appear inside it rb_str_cat(parser->output, token->start, TOKEN_LEN(token)); break; } // pop up to but not including the last BLOCKQUOTE on the scope stack if (IN(BLOCKQUOTE_START)) _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE_START, Qfalse); else _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE, Qfalse); // count number of BLOCKQUOTE tokens in line buffer and in scope stack ary_push(parser->line, type); i = ary_count(parser->line, BLOCKQUOTE); j = ary_count(parser->scope, BLOCKQUOTE); // decide whether we need to pop off excess BLOCKQUOTE tokens (will never need to push; that is handled above in the BLOCKQUOTE case itself) if (i < j) { // must pop (reduce nesting level) for (i = j - i; i > 0; i--) _Wikitext_pop_from_stack_up_to(parser, Qnil, BLOCKQUOTE, Qtrue); } // discard any whitespace here (so that "== foo ==" will be translated to " foo
" rather than "foo type == SPACE)) ; // discard ary_push(parser->scope, type); _Wikitext_indent(parser); // rather than repeat all that code for each kind of heading, share it and use a conditional here if (type == H6_START) rb_str_cat(parser->output, h6_start, sizeof(h6_start) - 1); else if (type == H5_START) rb_str_cat(parser->output, h5_start, sizeof(h5_start) - 1); else if (type == H4_START) rb_str_cat(parser->output, h4_start, sizeof(h4_start) - 1); else if (type == H3_START) rb_str_cat(parser->output, h3_start, sizeof(h3_start) - 1); else if (type == H2_START) rb_str_cat(parser->output, h2_start, sizeof(h2_start) - 1); else if (type == H1_START) rb_str_cat(parser->output, h1_start, sizeof(h1_start) - 1); // jump to top of the loop to process token we scanned during lookahead continue; case H6_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_h6, sizeof(literal_h6) - 1); } else { _Wikitext_rollback_failed_external_link(parser); // if any if (!IN(H6_START)) { // literal output only if not in h6 scope (we stay silent in that case) _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, literal_h6, sizeof(literal_h6) - 1); } } break; case H5_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_h5, sizeof(literal_h5) - 1); } else { _Wikitext_rollback_failed_external_link(parser); // if any if (!IN(H5_START)) { // literal output only if not in h5 scope (we stay silent in that case) _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, literal_h5, sizeof(literal_h5) - 1); } } break; case H4_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_h4, sizeof(literal_h4) - 1); } else { _Wikitext_rollback_failed_external_link(parser); // if any if (!IN(H4_START)) { // literal output only if not in h4 scope (we stay silent in that case) _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, literal_h4, sizeof(literal_h4) - 1); } } break; case H3_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_h3, sizeof(literal_h3) - 1); } else { _Wikitext_rollback_failed_external_link(parser); // if any if (!IN(H3_START)) { // literal output only if not in h3 scope (we stay silent in that case) _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, literal_h3, sizeof(literal_h3) - 1); } } break; case H2_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_h2, sizeof(literal_h2) - 1); } else { _Wikitext_rollback_failed_external_link(parser); // if any if (!IN(H2_START)) { // literal output only if not in h2 scope (we stay silent in that case) _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, literal_h2, sizeof(literal_h2) - 1); } } break; case H1_END: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, literal_h1, sizeof(literal_h1) - 1); } else { _Wikitext_rollback_failed_external_link(parser); // if any if (!IN(H1_START)) { // literal output only if not in h1 scope (we stay silent in that case) _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, literal_h1, sizeof(literal_h1) - 1); } } break; case MAIL: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, token->start, TOKEN_LEN(token)); } else { // in plain scope, will turn into autolink (with appropriate, user-configurable CSS) _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); i = TOKEN_TEXT(token); if (parser->autolink == Qtrue) i = _Wikitext_hyperlink(rb_str_new2("mailto:"), i, i, mailto_class); rb_str_append(parser->output, i); } break; case URI: if (IN(NO_WIKI_START)) // user can temporarily suppress autolinking by using
// note that unlike MediaWiki, we do allow autolinking inside PRE blocks rb_str_cat(parser->output, token->start, TOKEN_LEN(token)); else if (IN(LINK_START)) { // if the URI were allowed it would have been handled already in LINK_START _Wikitext_rollback_failed_link(parser); i = TOKEN_TEXT(token); if (parser->autolink == Qtrue) i = _Wikitext_hyperlink(Qnil, i, i, parser->external_link_class); // link target, link text rb_str_append(parser->output, i); } else if (IN(EXT_LINK_START)) { if (NIL_P(parser->link_target)) { // this must be our link target: look ahead to make sure we see the space we're expecting to see i = TOKEN_TEXT(token); NEXT_TOKEN(); if (token->type == SPACE) { ary_push(parser->scope, SPACE); parser->link_target = i; parser->link_text = rb_str_new2(""); parser->capture = parser->link_text; token = NULL; // silently consume space } else { // didn't see the space! this must be an error _Wikitext_pop_from_stack(parser, Qnil); _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, ext_link_start, sizeof(ext_link_start) - 1); if (parser->autolink == Qtrue) i = _Wikitext_hyperlink(Qnil, i, i, parser->external_link_class); // link target, link text rb_str_append(parser->output, i); } } else { if (NIL_P(parser->link_text)) // this must be the first part of our link text parser->link_text = TOKEN_TEXT(token); else // add to existing link text rb_str_cat(parser->link_text, token->start, TOKEN_LEN(token)); } } else { // in plain scope, will turn into autolink (with appropriate, user-configurable CSS) _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); i = TOKEN_TEXT(token); if (parser->autolink == Qtrue) i = _Wikitext_hyperlink(Qnil, i, i, parser->external_link_class); // link target, link text rb_str_append(parser->output, i); } break; // internal links (links to other wiki articles) look like this: // [[another article]] (would point at, for example, "/wiki/another_article") // [[the other article|the link text we'll use for it]] // [[the other article | the link text we'll use for it]] // note that the forward slash is a reserved character which changes the meaning of an internal link; // this is a link that is external to the wiki but internal to the site as a whole: // [[bug/12]] (a relative link to "/bug/12") // MediaWiki has strict requirements about what it will accept as a link target: // all wikitext markup is disallowed: // example [[foo ''bar'' baz]] // renders [[foo bar baz]] (ie. not a link) // example [[foo bar baz]] // renders [[foo bar baz]] (ie. not a link) // example [[foo '' baz]] // renders [[foo '' baz]] (ie. not a link) // example [[foobaz]] // renders [[foo <bar> baz]] (ie. not a link) // HTML entities and non-ASCII, however, make it through: // example [[foo €]] // renders foo € // example [[foo €]] // renders foo € // we'll impose similar restrictions here for the link target; allowed tokens will be: // SPACE, SPECIAL_URI_CHARS, PRINTABLE, ALNUM, DEFAULT, QUOT and AMP // everything else will be rejected case LINK_START: i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(i, link_start, sizeof(link_start) - 1); } else if (IN(EXT_LINK_START)) // already in external link scope! (and in fact, must be capturing link_text right now) rb_str_cat(i, link_start, sizeof(link_start) - 1); else if (IN(LINK_START)) { // already in internal link scope! this is a syntax error _Wikitext_rollback_failed_link(parser); rb_str_cat(parser->output, link_start, sizeof(link_start) - 1); } else if (IN(SEPARATOR)) { // scanning internal link text } else // not in internal link scope yet { // will either emit a link, or the rollback of a failed link, so start the para now _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); ary_push(parser->scope, LINK_START); // look ahead and try to gobble up link target while (NEXT_TOKEN(), (type = token->type)) { if (type == SPACE || type == SPECIAL_URI_CHARS || type == PRINTABLE || type == ALNUM || type == DEFAULT || type == QUOT || type == QUOT_ENTITY || type == AMP || type == AMP_ENTITY || type == IMG_START || type == IMG_END || type == LEFT_CURLY || type == RIGHT_CURLY) { // accumulate these tokens into link_target if (NIL_P(parser->link_target)) { parser->link_target = rb_str_new2(""); parser->capture = parser->link_target; } if (type == QUOT_ENTITY) // don't insert the entity, insert the literal quote rb_str_cat(parser->link_target, quote, sizeof(quote) - 1); else if (type == AMP_ENTITY) // don't insert the entity, insert the literal ampersand rb_str_cat(parser->link_target, ampersand, sizeof(ampersand) - 1); else rb_str_cat(parser->link_target, token->start, TOKEN_LEN(token)); } else if (type == LINK_END) break; // jump back to top of loop (will handle this in LINK_END case below) else if (type == SEPARATOR) { ary_push(parser->scope, SEPARATOR); parser->link_text = rb_str_new2(""); parser->capture = parser->link_text; token = NULL; break; } else // unexpected token (syntax error) { _Wikitext_rollback_failed_link(parser); break; // jump back to top of loop to handle unexpected token } } // jump to top of the loop to process token we scanned during lookahead (if any) continue; } break; case LINK_END: i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(i, link_end, sizeof(link_end) - 1); } else if (IN(EXT_LINK_START)) // already in external link scope! (and in fact, must be capturing link_text right now) rb_str_cat(i, link_end, sizeof(link_end) - 1); else if (IN(LINK_START)) { // in internal link scope! if (NIL_P(parser->link_text) || RSTRING_LEN(parser->link_text) == 0) // use link target as link text parser->link_text = _Wikitext_parser_sanitize_link_target(parser, Qfalse); else parser->link_text = _Wikitext_parser_trim_link_target(parser->link_text); _Wikitext_parser_encode_link_target(parser); _Wikitext_pop_from_stack_up_to(parser, i, LINK_START, Qtrue); parser->capture = Qnil; if (parser->special_link) i = _Wikitext_hyperlink(rb_str_new2("/"), parser->link_target, parser->link_text, Qnil); else i = _Wikitext_hyperlink(prefix, parser->link_target, parser->link_text, Qnil); rb_str_append(parser->output, i); parser->link_target = Qnil; parser->link_text = Qnil; } else // wasn't in internal link scope { _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, link_end, sizeof(link_end) - 1); } break; // external links look like this: // [http://google.com/ the link text] // strings in square brackets which don't match this syntax get passed through literally; eg: // he was very angery [sic] about the turn of events case EXT_LINK_START: i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(i, ext_link_start, sizeof(ext_link_start) - 1); } else if (IN(EXT_LINK_START)) // already in external link scope! (and in fact, must be capturing link_text right now) rb_str_cat(i, ext_link_start, sizeof(ext_link_start) - 1); else if (IN(LINK_START)) { // already in internal link scope! i = rb_str_new(ext_link_start, sizeof(ext_link_start) - 1); if (NIL_P(parser->link_target)) // this must be the first character of our link target parser->link_target = i; else if (IN(SPACE)) { // link target has already been scanned if (NIL_P(parser->link_text)) // this must be the first character of our link text parser->link_text = i; else // add to existing link text rb_str_append(parser->link_text, i); } else // add to existing link target rb_str_append(parser->link_target, i); } else // not in external link scope yet { // will either emit a link, or the rollback of a failed link, so start the para now _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); // look ahead: expect a URI NEXT_TOKEN(); if (token->type == URI) ary_push(parser->scope, EXT_LINK_START); // so far so good, jump back to the top of the loop else // only get here if there was a syntax error (missing URI) rb_str_cat(parser->output, ext_link_start, sizeof(ext_link_start) - 1); continue; // jump back to top of loop to handle token (either URI or whatever it is) } break; case EXT_LINK_END: i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(i, ext_link_end, sizeof(ext_link_end) - 1); } else if (IN(EXT_LINK_START)) { if (NIL_P(parser->link_text)) // syntax error: external link with no link text _Wikitext_rollback_failed_external_link(parser); else { // success! _Wikitext_pop_from_stack_up_to(parser, i, EXT_LINK_START, Qtrue); parser->capture = Qnil; i = _Wikitext_hyperlink(Qnil, parser->link_target, parser->link_text, parser->external_link_class); rb_str_append(parser->output, i); } parser->link_target = Qnil; parser->link_text = Qnil; } else { _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(parser->output, ext_link_end, sizeof(ext_link_end) - 1); } break; case SEPARATOR: i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, separator, sizeof(separator) - 1); break; case SPACE: i = NIL_P(parser->capture) ? parser->output : parser->capture; if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(i, token->start, TOKEN_LEN(token)); } else { // peek ahead to see next token char *token_ptr = token->start; int token_len = TOKEN_LEN(token); NEXT_TOKEN(); type = token->type; if (((type == H6_END) && IN(H6_START)) || ((type == H5_END) && IN(H5_START)) || ((type == H4_END) && IN(H4_START)) || ((type == H3_END) && IN(H3_START)) || ((type == H2_END) && IN(H2_START)) || ((type == H1_END) && IN(H1_START))) { // will suppress emission of space (discard) if next token is a H6_END, H5_END etc and we are in the corresponding scope } else { // emit the space _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, token_ptr, token_len); } // jump to top of the loop to process token we scanned during lookahead continue; } break; case QUOT_ENTITY: case AMP_ENTITY: case NAMED_ENTITY: case DECIMAL_ENTITY: // pass these through unaltered as they are case sensitive i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, token->start, TOKEN_LEN(token)); break; case HEX_ENTITY: // normalize hex entities (downcase them) i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_append(i, _Wikitext_downcase(TOKEN_TEXT(token))); break; case QUOT: i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, quot_entity, sizeof(quot_entity) - 1); break; case AMP: i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, amp_entity, sizeof(amp_entity) - 1); break; case LESS: i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, lt_entity, sizeof(lt_entity) - 1); break; case GREATER: i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, gt_entity, sizeof(gt_entity) - 1); break; case IMG_START: if (IN(NO_WIKI_START) || IN(PRE) || IN(PRE_START)) { _Wikitext_emit_pending_crlf_if_necessary(parser); rb_str_cat(parser->output, token->start, TOKEN_LEN(token)); } else if (!NIL_P(parser->capture)) rb_str_cat(parser->capture, token->start, TOKEN_LEN(token)); else { // not currently capturing: will be emitting something on success or failure, so get ready _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); // scan ahead consuming PRINTABLE, ALNUM and SPECIAL_URI_CHARS tokens // will cheat here and abuse the link_target capture buffer to accumulate text if (NIL_P(parser->link_target)) parser->link_target = rb_str_new2(""); while (NEXT_TOKEN(), (type = token->type)) { if (type == PRINTABLE || type == ALNUM || type == SPECIAL_URI_CHARS) rb_str_cat(parser->link_target, token->start, TOKEN_LEN(token)); else if (type == IMG_END) { // success _Wikitext_append_img(parser, RSTRING_PTR(parser->link_target), RSTRING_LEN(parser->link_target)); token = NULL; break; } else // unexpected token (syntax error) { // rollback rb_str_cat(parser->output, literal_img_start, sizeof(literal_img_start) - 1); rb_str_cat(parser->output, RSTRING_PTR(parser->link_target), RSTRING_LEN(parser->link_target)); break; } } // jump to top of the loop to process token we scanned during lookahead parser->link_target = Qnil; continue; } break; case CRLF: i = parser->pending_crlf; parser->pending_crlf = Qfalse; _Wikitext_rollback_failed_link(parser); // if any _Wikitext_rollback_failed_external_link(parser); // if any if (IN(NO_WIKI_START) || IN(PRE_START)) { ary_clear(parser->line_buffer); rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); break; } else if (IN(PRE)) { // beware when BLOCKQUOTE on line buffer (not line stack!) prior to CRLF, that must be end of PRE block if (ary_entry(parser->line_buffer, -2) == BLOCKQUOTE) // don't emit in this case _Wikitext_pop_from_stack_up_to(parser, parser->output, PRE, Qtrue); else { if (ary_entry(parser->line_buffer, -2) == PRE) { // only thing on line is the PRE: emit pending line ending (if we had one) if (i == Qtrue) rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); } // clear these _before_ calling NEXT_TOKEN (NEXT_TOKEN adds to the line_buffer) ary_clear(parser->line); ary_clear(parser->line_buffer); // peek ahead to see if this is definitely the end of the PRE block NEXT_TOKEN(); type = token->type; if (type != BLOCKQUOTE && type != PRE) // this is definitely the end of the block, so don't emit _Wikitext_pop_from_stack_up_to(parser, parser->output, PRE, Qtrue); else // potentially will emit parser->pending_crlf = Qtrue; continue; // jump back to top of loop to handle token grabbed via lookahead } } else { parser->pending_crlf = Qtrue; // count number of BLOCKQUOTE tokens in line buffer (can be zero) and pop back to that level // as a side effect, this handles any open span-level elements and unclosed blocks // (with special handling for P blocks and LI elements) i = ary_count(parser->line, BLOCKQUOTE) + ary_count(parser->scope, BLOCKQUOTE_START); for (j = parser->scope->count; j > i; j--) { if (parser->scope->count > 0 && ary_entry(parser->scope, -1) == LI) { parser->pending_crlf = Qfalse; break; } // special handling on last iteration through the loop if the top item on the scope is a P block if ((j - i == 1) && ary_entry(parser->scope, -1) == P) { // if nothing or BLOCKQUOTE on line buffer (not line stack!) prior to CRLF, this must be a paragraph break // (note that we have to make sure we're not inside a BLOCKQUOTE_START block // because in those blocks BLOCKQUOTE tokens have no special meaning) if (NO_ITEM(ary_entry(parser->line_buffer, -2)) || (ary_entry(parser->line_buffer, -2) == BLOCKQUOTE && !IN(BLOCKQUOTE_START))) // paragraph break parser->pending_crlf = Qfalse; else // not a paragraph break! continue; } _Wikitext_pop_from_stack(parser, Qnil); } } // delete the entire contents of the line scope stack and buffer ary_clear(parser->line); ary_clear(parser->line_buffer); break; case SPECIAL_URI_CHARS: case PRINTABLE: case ALNUM: case IMG_END: case LEFT_CURLY: case RIGHT_CURLY: i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_cat(i, token->start, TOKEN_LEN(token)); break; case DEFAULT: i = NIL_P(parser->capture) ? parser->output : parser->capture; _Wikitext_pop_excess_elements(parser); _Wikitext_start_para_if_necessary(parser); rb_str_append(i, _Wikitext_utf32_char_to_entity(token->code_point)); // convert to entity break; case END_OF_FILE: // special case for input like " foo\n " (see pre_spec.rb) if (IN(PRE) && ary_entry(parser->line_buffer, -2) == PRE && parser->pending_crlf == Qtrue) rb_str_cat(parser->output, parser->line_ending->ptr, parser->line_ending->len); // close any open scopes on hitting EOF _Wikitext_rollback_failed_external_link(parser); // if any _Wikitext_rollback_failed_link(parser); // if any for (i = 0, j = parser->scope->count; i < j; i++) _Wikitext_pop_from_stack(parser, Qnil); goto return_output; // break not enough here (want to break out of outer while loop, not inner switch statement) default: break; } // reset current token; forcing lexer to return another token at the top of the loop token = NULL; } while (1); return_output: return parser->output; }