diff options
Diffstat (limited to 'mandoc.c')
| -rw-r--r-- | mandoc.c | 444 |
1 files changed, 304 insertions, 140 deletions
@@ -35,199 +35,363 @@ static int a2time(time_t *, const char *, const char *); static char *time2a(time_t); +static int numescape(const char *); -int -mandoc_special(char *p) +/* + * Pass over recursive numerical expressions. This context of this + * function is important: it's only called within character-terminating + * escapes (e.g., \s[xxxyyy]), so all we need to do is handle initial + * recursion: we don't care about what's in these blocks. + * This returns the number of characters skipped or -1 if an error + * occurs (the caller should bail). + */ +static int +numescape(const char *start) +{ + int i; + size_t sz; + const char *cp; + + i = 0; + + /* The expression consists of a subexpression. */ + + if ('\\' == start[i]) { + cp = &start[++i]; + /* + * Read past the end of the subexpression. + * Bail immediately on errors. + */ + if (ESCAPE_ERROR == mandoc_escape(&cp, NULL, NULL)) + return(-1); + return(i + cp - &start[i]); + } + + if ('(' != start[i++]) + return(0); + + /* + * A parenthesised subexpression. Read until the closing + * parenthesis, making sure to handle any nested subexpressions + * that might ruin our parse. + */ + + while (')' != start[i]) { + sz = strcspn(&start[i], ")\\"); + i += (int)sz; + + if ('\0' == start[i]) + return(-1); + else if ('\\' != start[i]) + continue; + + cp = &start[++i]; + if (ESCAPE_ERROR == mandoc_escape(&cp, NULL, NULL)) + return(-1); + i += cp - &start[i]; + } + + /* Read past the terminating ')'. */ + return(++i); +} + +/* + * Handle an escaped sequeence. This should be called with any + * string subsequent a `\'. Pass a pointer to this substring as "end"; + * it will be set to the supremum of the parsed escape sequence. If + * this returns ESCAPE_ERROR, the string is bogus and should be thrown + * away. If not ESCAPE_ERROR or ESCAPE_IGNORE, "start" is set to the + * first relevant character of the substring (font, glyph, whatever) of + * length sz. Both "start" and "sz" may be NULL. + */ +enum mandoc_esc +mandoc_escape(const char **end, const char **start, int *sz) { - int len, i; - char term; - char *sv; - - len = 0; + char c, term, numeric; + int i, lim, ssz, rlim; + const char *cp, *rstart; + enum mandoc_esc gly; + + cp = *end; + rstart = cp; + if (start) + *start = rstart; + i = 0; + gly = ESCAPE_ERROR; term = '\0'; - sv = p; + numeric = 0; - assert('\\' == *p); - p++; + switch ((c = cp[i++])) { + /* + * First the glyphs. There are several different forms of + * these, but each eventually returns a substring of the glyph + * name. + */ + case ('('): + gly = ESCAPE_SPECIAL; + lim = 2; + break; + case ('['): + gly = ESCAPE_SPECIAL; + term = ']'; + break; + case ('C'): + if ('\'' != cp[i]) + return(ESCAPE_ERROR); + gly = ESCAPE_SPECIAL; + term = '\''; + break; - switch (*p++) { -#if 0 - case ('Z'): + /* + * Handle all triggers matching \X(xy, \Xx, and \X[xxxx], where + * 'X' is the trigger. These have opaque sub-strings. + */ + case ('F'): /* FALLTHROUGH */ - case ('X'): + case ('g'): /* FALLTHROUGH */ - case ('x'): + case ('k'): /* FALLTHROUGH */ - case ('S'): + case ('M'): /* FALLTHROUGH */ - case ('R'): + case ('m'): /* FALLTHROUGH */ - case ('N'): + case ('n'): /* FALLTHROUGH */ - case ('l'): + case ('V'): /* FALLTHROUGH */ - case ('L'): + case ('Y'): + if (ESCAPE_ERROR == gly) + gly = ESCAPE_IGNORE; /* FALLTHROUGH */ - case ('H'): + case ('*'): + if (ESCAPE_ERROR == gly) + gly = ESCAPE_PREDEF; /* FALLTHROUGH */ - case ('h'): + case ('f'): + if (ESCAPE_ERROR == gly) + gly = ESCAPE_FONT; + + rstart= &cp[i]; + if (start) + *start = rstart; + + switch (cp[i++]) { + case ('('): + lim = 2; + break; + case ('['): + term = ']'; + break; + default: + lim = 1; + i--; + break; + } + break; + + /* + * These escapes are of the form \X'Y', where 'X' is the trigger + * and 'Y' is any string. These have opaque sub-strings. + */ + case ('A'): /* FALLTHROUGH */ - case ('D'): + case ('b'): /* FALLTHROUGH */ - case ('C'): + case ('D'): /* FALLTHROUGH */ - case ('b'): + case ('o'): /* FALLTHROUGH */ - case ('B'): + case ('R'): /* FALLTHROUGH */ - case ('a'): + case ('X'): /* FALLTHROUGH */ - case ('A'): - if (*p++ != '\'') - return(0); + case ('Z'): + if ('\'' != cp[i++]) + return(ESCAPE_ERROR); + gly = ESCAPE_IGNORE; term = '\''; break; -#endif + + /* + * These escapes are of the form \X'N', where 'X' is the trigger + * and 'N' resolves to a numerical expression. + */ + case ('B'): + /* FALLTHROUGH */ case ('h'): /* FALLTHROUGH */ + case ('H'): + /* FALLTHROUGH */ + case ('L'): + /* FALLTHROUGH */ + case ('l'): + /* FALLTHROUGH */ + case ('N'): + if (ESCAPE_ERROR == gly) + gly = ESCAPE_NUMBERED; + /* FALLTHROUGH */ + case ('S'): + /* FALLTHROUGH */ case ('v'): /* FALLTHROUGH */ + case ('w'): + /* FALLTHROUGH */ + case ('x'): + if (ESCAPE_ERROR == gly) + gly = ESCAPE_IGNORE; + if ('\'' != cp[i++]) + return(ESCAPE_ERROR); + term = numeric = '\''; + break; + + /* + * Sizes get a special category of their own. + */ case ('s'): - if (ASCII_HYPH == *p) - *p = '-'; + gly = ESCAPE_IGNORE; - i = 0; - if ('+' == *p || '-' == *p) { - p++; - i = 1; - } + rstart = &cp[i]; + if (start) + *start = rstart; + + /* See +/- counts as a sign. */ + c = cp[i]; + if ('+' == c || '-' == c || ASCII_HYPH == c) + ++i; - switch (*p++) { + switch (cp[i++]) { case ('('): - len = 2; + lim = 2; break; case ('['): - term = ']'; + term = numeric = ']'; break; case ('\''): - term = '\''; + term = numeric = '\''; break; - case ('0'): - i = 1; - /* FALLTHROUGH */ default: - len = 1; - p--; + lim = 1; + i--; break; } - if (ASCII_HYPH == *p) - *p = '-'; - if ('+' == *p || '-' == *p) { - if (i) - return(0); - p++; - } - - /* Handle embedded numerical subexp or escape. */ - - if ('(' == *p) { - while (*p && ')' != *p) - if ('\\' == *p++) { - i = mandoc_special(--p); - if (0 == i) - return(0); - p += i; - } - - if (')' == *p++) - break; + /* See +/- counts as a sign. */ + c = cp[i]; + if ('+' == c || '-' == c || ASCII_HYPH == c) + ++i; - return(0); - } else if ('\\' == *p) { - if (0 == (i = mandoc_special(p))) - return(0); - p += i; - } + break; + /* + * Anything else is assumed to be a glyph. + */ + default: + gly = ESCAPE_SPECIAL; + lim = 1; + i--; break; -#if 0 - case ('Y'): - /* FALLTHROUGH */ - case ('V'): - /* FALLTHROUGH */ - case ('$'): - /* FALLTHROUGH */ - case ('n'): - /* FALLTHROUGH */ -#endif - case ('k'): - /* FALLTHROUGH */ - case ('M'): - /* FALLTHROUGH */ - case ('m'): - /* FALLTHROUGH */ - case ('f'): - /* FALLTHROUGH */ - case ('F'): - /* FALLTHROUGH */ - case ('*'): - switch (*p++) { - case ('('): - len = 2; + } + + assert(ESCAPE_ERROR != gly); + + rstart = &cp[i]; + if (start) + *start = rstart; + + /* + * If a terminating block has been specified, we need to + * handle the case of recursion, which could have their + * own terminating blocks that mess up our parse. This, by the + * way, means that the "start" and "size" values will be + * effectively meaningless. + */ + + ssz = 0; + if (numeric && -1 == (ssz = numescape(&cp[i]))) + return(ESCAPE_ERROR); + + i += ssz; + rlim = -1; + + /* + * We have a character terminator. Try to read up to that + * character. If we can't (i.e., we hit the nil), then return + * an error; if we can, calculate our length, read past the + * terminating character, and exit. + */ + + if ('\0' != term) { + *end = strchr(&cp[i], term); + if ('\0' == *end) + return(ESCAPE_ERROR); + + rlim = *end - &cp[i]; + if (sz) + *sz = rlim; + (*end)++; + goto out; + } + + assert(lim > 0); + + /* + * We have a numeric limit. If the string is shorter than that, + * stop and return an error. Else adjust our endpoint, length, + * and return the current glyph. + */ + + if ((size_t)lim > strlen(&cp[i])) + return(ESCAPE_ERROR); + + rlim = lim; + if (sz) + *sz = rlim; + + *end = &cp[i] + lim; + +out: + assert(rlim >= 0 && rstart); + + /* Run post-processors. */ + + switch (gly) { + case (ESCAPE_FONT): + if (1 != rlim) break; - case ('['): - term = ']'; + switch (*rstart) { + case ('3'): + /* FALLTHROUGH */ + case ('B'): + gly = ESCAPE_FONTBOLD; break; - default: - len = 1; - p--; + case ('2'): + /* FALLTHROUGH */ + case ('I'): + gly = ESCAPE_FONTITALIC; break; - } - break; - case ('('): - len = 2; - break; - case ('['): - term = ']'; - break; - case ('z'): - len = 1; - if ('\\' == *p) { - if (0 == (i = mandoc_special(p))) - return(0); - p += i; - return(*p ? (int)(p - sv) : 0); - } - break; - case ('o'): - /* FALLTHROUGH */ - case ('w'): - if ('\'' == *p++) { - term = '\''; + case ('P'): + gly = ESCAPE_FONTPREV; + break; + case ('1'): + /* FALLTHROUGH */ + case ('R'): + gly = ESCAPE_FONTROMAN; break; } - /* FALLTHROUGH */ + case (ESCAPE_SPECIAL): + if (1 != rlim) + break; + if ('c' == *rstart) + gly = ESCAPE_NOSPACE; + break; default: - len = 1; - p--; break; } - if (term) { - for ( ; *p && term != *p; p++) - if (ASCII_HYPH == *p) - *p = '-'; - return(*p ? (int)(p - sv) : 0); - } - - for (i = 0; *p && i < len; i++, p++) - if (ASCII_HYPH == *p) - *p = '-'; - return(i == len ? (int)(p - sv) : 0); + return(gly); } - void * mandoc_calloc(size_t num, size_t size) { |