/* $OpenBSD: compile.c,v 1.30 2009/10/23 15:24:41 reyk Exp $ */ /*- * Copyright (c) 1992 Diomidis Spinellis. * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Diomidis Spinellis of Imperial College, University of London. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint /* from: static char sccsid[] = "@(#)compile.c 8.2 (Berkeley) 4/28/95"; */ static const char rcsid[] = "$OpenBSD: compile.c,v 1.30 2009/10/23 15:24:41 reyk Exp $"; #endif /* not lint */ #include #include #include #include #include #include #include #include #include #include #include "defs.h" #include "extern.h" #define LHSZ 128 #define LHMASK (LHSZ - 1) static struct labhash { struct labhash *lh_next; u_int lh_hash; struct s_command *lh_cmd; int lh_ref; } *labels[LHSZ]; static char *compile_addr(char *, struct s_addr *); static char *compile_ccl(char **, char *); static char *compile_delimited(char *, char *); static char *compile_flags(char *, struct s_subst *); static char *compile_re(char *, regex_t **); static char *compile_subst(char *, struct s_subst *); static char *compile_text(void); static char *compile_tr(char *, char **); static struct s_command **compile_stream(struct s_command **); static char *duptoeol(char *, char *, char **); static void enterlabel(struct s_command *); static struct s_command *findlabel(char *); static void fixuplabel(struct s_command *, struct s_command *); static void uselabel(void); /* * Command specification. This is used to drive the command parser. */ struct s_format { char code; /* Command code */ int naddr; /* Number of address args */ enum e_args args; /* Argument type */ }; static struct s_format cmd_fmts[] = { {'{', 2, GROUP}, {'}', 0, ENDGROUP}, {'a', 1, TEXT}, {'b', 2, BRANCH}, {'c', 2, TEXT}, {'d', 2, EMPTY}, {'D', 2, EMPTY}, {'g', 2, EMPTY}, {'G', 2, EMPTY}, {'h', 2, EMPTY}, {'H', 2, EMPTY}, {'i', 1, TEXT}, {'l', 2, EMPTY}, {'n', 2, EMPTY}, {'N', 2, EMPTY}, {'p', 2, EMPTY}, {'P', 2, EMPTY}, {'q', 1, EMPTY}, {'r', 1, RFILE}, {'s', 2, SUBST}, {'t', 2, BRANCH}, {'w', 2, WFILE}, {'x', 2, EMPTY}, {'y', 2, TR}, {'!', 2, NONSEL}, {':', 0, LABEL}, {'#', 0, COMMENT}, {'=', 1, EMPTY}, {'\0', 0, COMMENT}, }; /* The compiled program. */ struct s_command *prog; /* * Compile the program into prog. * Initialise appends. */ void compile(void) { *compile_stream(&prog) = NULL; fixuplabel(prog, NULL); uselabel(); appends = xmalloc(sizeof(struct s_appends) * appendnum); match = xmalloc((maxnsub + 1) * sizeof(regmatch_t)); } #define EATSPACE() do { \ if (p) \ while (isascii(*p) && isspace(*p)) \ p++; \ } while (0) static struct s_command ** compile_stream(struct s_command **link) { char *p; static char *lbuf; /* To avoid excessive malloc calls */ static size_t bufsize; struct s_command *cmd, *cmd2, *stack; struct s_format *fp; int naddr; /* Number of addresses */ stack = 0; for (;;) { if ((p = cu_fgets(&lbuf, &bufsize)) == NULL) { if (stack != 0) err(COMPILE, "unexpected EOF (pending }'s)"); return (link); } semicolon: EATSPACE(); if (*p == '#' || *p == '\0') continue; if (*p == ';') { p++; goto semicolon; } *link = cmd = xmalloc(sizeof(struct s_command)); link = &cmd->next; cmd->nonsel = cmd->inrange = 0; /* First parse the addresses */ naddr = 0; /* Valid characters to start an address */ #define addrchar(c) (strchr("0123456789/\\$", (c))) if (addrchar(*p)) { naddr++; cmd->a1 = xmalloc(sizeof(struct s_addr)); p = compile_addr(p, cmd->a1); EATSPACE(); /* EXTENSION */ if (*p == ',') { p++; EATSPACE(); /* EXTENSION */ naddr++; cmd->a2 = xmalloc(sizeof(struct s_addr)); p = compile_addr(p, cmd->a2); EATSPACE(); } else { cmd->a2 = 0; } } else { cmd->a1 = cmd->a2 = 0; } nonsel: /* Now parse the command */ if (!*p) err(COMPILE, "command expected"); cmd->code = *p; for (fp = cmd_fmts; fp->code; fp++) if (fp->code == *p) break; if (!fp->code) err(COMPILE, "invalid command code %c", *p); if (naddr > fp->naddr) err(COMPILE, "command %c expects up to %d address(es), found %d", *p, fp->naddr, naddr); switch (fp->args) { case NONSEL: /* ! */ p++; EATSPACE(); cmd->nonsel = ! cmd->nonsel; goto nonsel; case GROUP: /* { */ p++; EATSPACE(); cmd->next = stack; stack = cmd; link = &cmd->u.c; if (*p) goto semicolon; break; case ENDGROUP: /* * Short-circuit command processing, since end of * group is really just a noop. */ cmd->nonsel = 1; if (stack == 0) err(COMPILE, "unexpected }"); cmd2 = stack; stack = cmd2->next; cmd2->next = cmd; /*FALLTHROUGH*/ case EMPTY: /* d D g G h H l n N p P q x = \0 */ p++; EATSPACE(); if (*p == ';') { p++; link = &cmd->next; goto semicolon; } if (*p) err(COMPILE, "extra characters at the end of %c command", cmd->code); break; case TEXT: /* a c i */ p++; EATSPACE(); if (*p != '\\') err(COMPILE, "command %c expects \\ followed by" " text", cmd->code); p++; EATSPACE(); if (*p) err(COMPILE, "extra characters after \\ at the" " end of %c command", cmd->code); cmd->t = compile_text(); break; case COMMENT: /* \0 # */ break; case WFILE: /* w */ p++; EATSPACE(); if (*p == '\0') err(COMPILE, "filename expected"); cmd->t = duptoeol(p, "w command", NULL); if (aflag) cmd->u.fd = -1; else if ((cmd->u.fd = open(p, O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1) err(FATAL, "%s: %s", p, strerror(errno)); break; case RFILE: /* r */ p++; EATSPACE(); cmd->t = duptoeol(p, "read command", NULL); break; case BRANCH: /* b t */ p++; EATSPACE(); if (*p == '\0') cmd->t = NULL; else cmd->t = duptoeol(p, "branch", &p); if (*p == ';') { p++; goto semicolon; } break; case LABEL: /* : */ p++; EATSPACE(); cmd->t = duptoeol(p, "label", &p); if (strlen(cmd->t) == 0) err(COMPILE, "empty label"); enterlabel(cmd); if (*p == ';') { p++; goto semicolon; } break; case SUBST: /* s */ p++; if (*p == '\0' || *p == '\\') err(COMPILE, "substitute pattern can not be" " delimited by newline or backslash"); cmd->u.s = xmalloc(sizeof(struct s_subst)); p = compile_re(p, &cmd->u.s->re); if (p == NULL) err(COMPILE, "unterminated substitute pattern"); --p; p = compile_subst(p, cmd->u.s); p = compile_flags(p, cmd->u.s); EATSPACE(); if (*p == ';') { p++; link = &cmd->next; goto semicolon; } break; case TR: /* y */ p++; p = compile_tr(p, (char **)&cmd->u.y); EATSPACE(); if (*p == ';') { p++; link = &cmd->next; goto semicolon; } if (*p) err(COMPILE, "extra text at the end of a" " transform command"); break; } } } /* * Get a delimited string. P points to the delimeter of the string; d points * to a buffer area. Newline and delimiter escapes are processed; other * escapes are ignored. * * Returns a pointer to the first character after the final delimiter or NULL * in the case of a non-terminated string. The character array d is filled * with the processed string. */ static char * compile_delimited(char *p, char *d) { char c; c = *p++; if (c == '\0') return (NULL); else if (c == '\\') err(COMPILE, "\\ can not be used as a string delimiter"); else if (c == '\n') err(COMPILE, "newline can not be used as a string delimiter"); while (*p) { if (*p == '[') { if ((d = compile_ccl(&p, d)) == NULL) err(COMPILE, "unbalanced brackets ([])"); continue; } else if (*p == '\\' && p[1] == '[') { *d++ = *p++; } else if (*p == '\\' && p[1] == c) { p++; } else if (*p == '\\' && p[1] == 'n') { *d++ = '\n'; p += 2; continue; } else if (*p == '\\' && p[1] == '\\') { *d++ = *p++; } else if (*p == c) { *d = '\0'; return (p + 1); } *d++ = *p++; } return (NULL); } /* compile_ccl: expand a POSIX character class */ static char * compile_ccl(char **sp, char *t) { int c, d; char *s = *sp; *t++ = *s++; if (*s == '^') *t++ = *s++; if (*s == ']') *t++ = *s++; for (; *s && (*t = *s) != ']'; s++, t++) if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) { *++t = *++s, t++, s++; for (c = *s; (*t = *s) != ']' || c != d; s++, t++) if ((c = *s) == '\0') return NULL; } else if (*s == '\\' && s[1] == 'n') { *t = '\n'; s++; } if (*s == ']') { *sp = ++s; return (++t); } else { return (NULL); } } /* * Get a regular expression. P points to the delimiter of the regular * expression; repp points to the address of a regexp pointer. Newline * and delimiter escapes are processed; other escapes are ignored. * Returns a pointer to the first character after the final delimiter * or NULL in the case of a non terminated regular expression. The regexp * pointer is set to the compiled regular expression. * Cflags are passed to regcomp. */ static char * compile_re(char *p, regex_t **repp) { int eval; char *re; re = xmalloc(strlen(p) + 1); /* strlen(re) <= strlen(p) */ p = compile_delimited(p, re); if (p && strlen(re) == 0) { *repp = NULL; free(re); return (p); } *repp = xmalloc(sizeof(regex_t)); if (p && (eval = regcomp(*repp, re, Eflag ? REG_EXTENDED : 0)) != 0) err(COMPILE, "RE error: %s", strregerror(eval, *repp)); if (maxnsub < (*repp)->re_nsub) maxnsub = (*repp)->re_nsub; free(re); return (p); } /* * Compile the substitution string of a regular expression and set res to * point to a saved copy of it. Nsub is the number of parenthesized regular * expressions. */ static char * compile_subst(char *p, struct s_subst *s) { static char *lbuf; static size_t bufsize; int asize, ref, size; char c, *text, *op, *sp; int sawesc = 0; c = *p++; /* Terminator character */ if (c == '\0') return (NULL); s->maxbref = 0; s->linenum = linenum; text = NULL; asize = size = 0; do { size_t len = ROUNDLEN(strlen(p) + 1); if (asize - size < len) { do { asize += len; } while (asize - size < len); text = xrealloc(text, asize); } op = sp = text + size; for (; *p; p++) { if (*p == '\\' || sawesc) { /* * If this is a continuation from the last * buffer, we won't have a character to * skip over. */ if (sawesc) sawesc = 0; else p++; if (*p == '\0') { /* * This escaped character is continued * in the next part of the line. Note * this fact, then cause the loop to * exit w/ normal EOL case and reenter * above with the new buffer. */ sawesc = 1; p--; continue; } else if (strchr("123456789", *p) != NULL) { *sp++ = '\\'; ref = *p - '0'; if (s->re != NULL && ref > s->re->re_nsub) err(COMPILE, "\\%c not defined in the RE", *p); if (s->maxbref < ref) s->maxbref = ref; } else if (*p == '&' || *p == '\\') *sp++ = '\\'; } else if (*p == c) { p++; *sp++ = '\0'; size += sp - op; s->new = xrealloc(text, size); return (p); } else if (*p == '\n') { err(COMPILE, "unescaped newline inside substitute pattern"); /* NOTREACHED */ } *sp++ = *p; } size += sp - op; } while ((p = cu_fgets(&lbuf, &bufsize))); err(COMPILE, "unterminated substitute in regular expression"); /* NOTREACHED */ } /* * Compile the flags of the s command */ static char * compile_flags(char *p, struct s_subst *s) { int gn; /* True if we have seen g or n */ long l; char wfile[PATH_MAX], *q; s->n = 1; /* Default */ s->p = 0; s->wfile = NULL; s->wfd = -1; for (gn = 0;;) { EATSPACE(); /* EXTENSION */ switch (*p) { case 'g': if (gn) err(COMPILE, "more than one number or 'g' in" " substitute flags"); gn = 1; s->n = 0; break; case '\0': case '\n': case ';': return (p); case 'p': s->p = 1; break; case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': if (gn) err(COMPILE, "more than one number or 'g' in" " substitute flags"); gn = 1; l = strtol(p, &p, 10); if (l <= 0 || l >= INT_MAX) err(COMPILE, "number in substitute flags out of range"); s->n = (int)l; continue; case 'w': p++; #ifdef HISTORIC_PRACTICE if (*p != ' ') { err(WARNING, "space missing before w wfile"); return (p); } #endif EATSPACE(); q = wfile; while (*p) { if (*p == '\n') break; *q++ = *p++; } *q = '\0'; if (q == wfile) err(COMPILE, "no wfile specified"); s->wfile = strdup(wfile); if (!aflag && (s->wfd = open(wfile, O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1) err(FATAL, "%s: %s", wfile, strerror(errno)); return (p); default: err(COMPILE, "bad flag in substitute command: '%c'", *p); break; } p++; } } /* * Compile a translation set of strings into a lookup table. */ static char * compile_tr(char *p, char **transtab) { int i; char *lt, *op, *np; char *old = NULL, *new = NULL; if (*p == '\0' || *p == '\\') err(COMPILE, "transform pattern can not be delimited by newline or backslash"); old = xmalloc(strlen(p) + 1); p = compile_delimited(p, old); if (p == NULL) { err(COMPILE, "unterminated transform source string"); goto bad; } new = xmalloc(strlen(p) + 1); p = compile_delimited(--p, new); if (p == NULL) { err(COMPILE, "unterminated transform target string"); goto bad; } EATSPACE(); if (strlen(new) != strlen(old)) { err(COMPILE, "transform strings are not the same length"); goto bad; } /* We assume characters are 8 bits */ lt = xmalloc(UCHAR_MAX + 1); for (i = 0; i <= UCHAR_MAX; i++) lt[i] = (char)i; for (op = old, np = new; *op; op++, np++) lt[(u_char)*op] = *np; *transtab = lt; free(old); free(new); return (p); bad: free(old); free(new); return (NULL); } /* * Compile the text following an a, c, or i command. */ static char * compile_text(void) { int asize, esc_nl, size; char *lbuf, *text, *p, *op, *s; size_t bufsize; lbuf = text = NULL; asize = size = 0; while ((p = cu_fgets(&lbuf, &bufsize))) { size_t len = ROUNDLEN(strlen(p) + 1); if (asize - size < len) { do { asize += len; } while (asize - size < len); text = xrealloc(text, asize); } op = s = text + size; for (esc_nl = 0; *p != '\0'; p++) { if (*p == '\\' && p[1] != '\0' && *++p == '\n') esc_nl = 1; *s++ = *p; } size += s - op; if (!esc_nl) { *s = '\0'; break; } } free(lbuf); text[size] = '\0'; return (xrealloc(text, size + 1)); } /* * Get an address and return a pointer to the first character after * it. Fill the structure pointed to according to the address. */ static char * compile_addr(char *p, struct s_addr *a) { char *end; switch (*p) { case '\\': /* Context address */ ++p; /* FALLTHROUGH */ case '/': /* Context address */ p = compile_re(p, &a->u.r); if (p == NULL) err(COMPILE, "unterminated regular expression"); a->type = AT_RE; return (p); case '$': /* Last line */ a->type = AT_LAST; return (p + 1); /* Line number */ case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': a->type = AT_LINE; a->u.l = strtoul(p, &end, 10); return (end); default: err(COMPILE, "expected context address"); return (NULL); } } /* * duptoeol -- * Return a copy of all the characters up to \n or \0. */ static char * duptoeol(char *s, char *ctype, char **semi) { size_t len; int ws; char *start; ws = 0; if (semi) { for (start = s; *s != '\0' && *s != '\n' && *s != ';'; ++s) ws = isspace(*s); } else { for (start = s; *s != '\0' && *s != '\n'; ++s) ws = isspace(*s); *s = '\0'; } if (ws) err(WARNING, "whitespace after %s", ctype); len = s - start + 1; if (semi) *semi = s; s = xmalloc(len); strlcpy(s, start, len); return (s); } /* * Convert goto label names to addresses, and count a and r commands, in * the given subset of the script. Free the memory used by labels in b * and t commands (but not by :). * * TODO: Remove } nodes */ static void fixuplabel(struct s_command *cp, struct s_command *end) { for (; cp != end; cp = cp->next) switch (cp->code) { case 'a': case 'r': appendnum++; break; case 'b': case 't': /* Resolve branch target. */ if (cp->t == NULL) { cp->u.c = NULL; break; } if ((cp->u.c = findlabel(cp->t)) == NULL) err(COMPILE2, "undefined label '%s'", cp->t); free(cp->t); break; case '{': /* Do interior commands. */ fixuplabel(cp->u.c, cp->next); break; } } /* * Associate the given command label for later lookup. */ static void enterlabel(struct s_command *cp) { struct labhash **lhp, *lh; u_char *p; u_int h, c; for (h = 0, p = (u_char *)cp->t; (c = *p) != 0; p++) h = (h << 5) + h + c; lhp = &labels[h & LHMASK]; for (lh = *lhp; lh != NULL; lh = lh->lh_next) if (lh->lh_hash == h && strcmp(cp->t, lh->lh_cmd->t) == 0) err(COMPILE2, "duplicate label '%s'", cp->t); lh = xmalloc(sizeof *lh); lh->lh_next = *lhp; lh->lh_hash = h; lh->lh_cmd = cp; lh->lh_ref = 0; *lhp = lh; } /* * Find the label contained in the command l in the command linked * list cp. L is excluded from the search. Return NULL if not found. */ static struct s_command * findlabel(char *name) { struct labhash *lh; u_char *p; u_int h, c; for (h = 0, p = (u_char *)name; (c = *p) != 0; p++) h = (h << 5) + h + c; for (lh = labels[h & LHMASK]; lh != NULL; lh = lh->lh_next) { if (lh->lh_hash == h && strcmp(name, lh->lh_cmd->t) == 0) { lh->lh_ref = 1; return (lh->lh_cmd); } } return (NULL); } /* * Warn about any unused labels. As a side effect, release the label hash * table space. */ static void uselabel(void) { struct labhash *lh, *next; int i; for (i = 0; i < LHSZ; i++) { for (lh = labels[i]; lh != NULL; lh = next) { next = lh->lh_next; if (!lh->lh_ref) err(WARNING, "unused label '%s'", lh->lh_cmd->t); free(lh); } } }