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Diffstat (limited to 'src/libs/libgroff/nametoindex.cpp')
| -rw-r--r-- | src/libs/libgroff/nametoindex.cpp | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/src/libs/libgroff/nametoindex.cpp b/src/libs/libgroff/nametoindex.cpp new file mode 100644 index 0000000..095a432 --- /dev/null +++ b/src/libs/libgroff/nametoindex.cpp @@ -0,0 +1,167 @@ +/* Copyright (C) 1989-2020 Free Software Foundation, Inc. + Written by James Clark (jjc@jclark.com) + +This file is part of groff. + +groff is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation, either version 3 of the License, or +(at your option) any later version. + +groff is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received a copy of the GNU General Public License +along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "lib.h" + +#include <assert.h> +#include <ctype.h> +#include <stdlib.h> + +#include "errarg.h" +#include "error.h" +#include "font.h" +#include "ptable.h" +#include "itable.h" + +// Every glyphinfo is actually a charinfo. +class charinfo : glyph { +public: + const char *name; // The glyph name, or a null pointer. + friend class character_indexer; +}; + +// PTABLE(charinfo) is a hash table mapping 'const char *' to 'charinfo *'. +declare_ptable(charinfo) +implement_ptable(charinfo) + +// ITABLE(charinfo) is a hash table mapping 'int >= 0' to 'charinfo *'. +declare_itable(charinfo) +implement_itable(charinfo) + +// This class is as a registry storing all named and numbered glyphs known +// so far, and assigns a unique index to each glyph. +class character_indexer { +public: + character_indexer(); + ~character_indexer(); + // --------------------- Lookup or creation of a glyph. + glyph *ascii_char_glyph(unsigned char); + glyph *named_char_glyph(const char *); + glyph *numbered_char_glyph(int); +private: + int next_index; // Number of glyphs already allocated. + PTABLE(charinfo) table; // Table mapping name to glyph. + glyph *ascii_glyph[256]; // Shorthand table for looking up "charNNN" + // glyphs. + ITABLE(charinfo) ntable; // Table mapping number to glyph. + enum { NSMALL = 256 }; + glyph *small_number_glyph[NSMALL]; // Shorthand table for looking up + // numbered glyphs with small numbers. +}; + +character_indexer::character_indexer() +: next_index(0) +{ + int i; + for (i = 0; i < 256; i++) + ascii_glyph[i] = UNDEFINED_GLYPH; + for (i = 0; i < NSMALL; i++) + small_number_glyph[i] = UNDEFINED_GLYPH; +} + +character_indexer::~character_indexer() +{ +} + +glyph *character_indexer::ascii_char_glyph(unsigned char c) +{ + if (ascii_glyph[c] == UNDEFINED_GLYPH) { + char buf[4+3+1]; + memcpy(buf, "char", 4); + strcpy(buf + 4, i_to_a(c)); + charinfo *ci = new charinfo; + ci->index = next_index++; + ci->number = -1; + ci->name = strsave(buf); + ascii_glyph[c] = ci; + } + return ascii_glyph[c]; +} + +inline glyph *character_indexer::named_char_glyph(const char *s) +{ + // Glyphs with name 'charNNN' are only stored in ascii_glyph[], not + // in the table. Therefore treat them specially here. + if (s[0] == 'c' && s[1] == 'h' && s[2] == 'a' && s[3] == 'r') { + char *val; + long n = strtol(s + 4, &val, 10); + if (val != s + 4 && *val == '\0' && n >= 0 && n < 256) + return ascii_char_glyph((unsigned char)n); + } + charinfo *ci = table.lookupassoc(&s); + if (0 == ci) { + ci = new charinfo[1]; + ci->index = next_index++; + ci->number = -1; + ci->name = table.define(s, ci); + } + return ci; +} + +inline glyph *character_indexer::numbered_char_glyph(int n) +{ + if (n >= 0 && n < NSMALL) { + if (small_number_glyph[n] == UNDEFINED_GLYPH) { + charinfo *ci = new charinfo; + ci->index = next_index++; + ci->number = n; + ci->name = 0; + small_number_glyph[n] = ci; + } + return small_number_glyph[n]; + } + charinfo *ci = ntable.lookup(n); + if (0 == ci) { + ci = new charinfo[1]; + ci->index = next_index++; + ci->number = n; + ci->name = 0; + ntable.define(n, ci); + } + return ci; +} + +static character_indexer indexer; + +glyph *number_to_glyph(int n) +{ + return indexer.numbered_char_glyph(n); +} + +// troff overrides this function with its own version. + +glyph *name_to_glyph(const char *s) +{ + assert(s != 0 && s[0] != '\0' && s[0] != ' '); + if (s[1] == '\0') + // \200 and char128 are synonyms + return indexer.ascii_char_glyph(s[0]); + return indexer.named_char_glyph(s); +} + +const char *glyph_to_name(glyph *g) +{ + charinfo *ci = (charinfo *)g; // Every glyph is actually a charinfo. + return ci->name; +} + +// Local Variables: +// fill-column: 72 +// mode: C++ +// End: +// vim: set cindent noexpandtab shiftwidth=2 textwidth=72: |