/commands/sed/compile.c
C | 859 lines | 649 code | 50 blank | 160 comment | 228 complexity | a84283939ab51a156321b30c9cd28f50 MD5 | raw file
Possible License(s): AGPL-1.0, BSD-3-Clause
- /* $NetBSD: compile.c,v 1.35 2007/04/17 20:30:29 christos Exp $ */
- /*-
- * 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.
- */
- /*-
- * Copyright (c) 1992 Diomidis Spinellis.
- *
- * 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. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. 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.
- */
- #if HAVE_NBTOOL_CONFIG_H
- #include "nbtool_config.h"
- #endif
- #include <sys/cdefs.h>
- #include <sys/types.h>
- #include <sys/stat.h>
- #include <ctype.h>
- #include <errno.h>
- #include <fcntl.h>
- #include <limits.h>
- #include <regex.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include "defs.h"
- #include "extern.h"
- #ifndef _POSIX2_LINE_MAX
- #define _POSIX2_LINE_MAX (2 * BUFSIZ)
- #endif
- #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 *);
- 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();
- if (appendnum > 0)
- appends = xmalloc(sizeof(struct s_appends) * appendnum);
- match = xmalloc((maxnsub + 1) * sizeof(regmatch_t));
- }
- #define EATSPACE() \
- while (*p && isascii((unsigned char)*p) && \
- isspace((unsigned char)*p)) \
- p++ \
- static struct s_command **
- compile_stream(struct s_command **link)
- {
- char *p;
- static char lbuf[_POSIX2_LINE_MAX + 1]; /* To save stack */
- struct s_command *cmd, *cmd2, *stack;
- struct s_format *fp;
- int naddr; /* Number of addresses */
- stack = 0;
- for (;;) {
- if ((p = cu_fgets(lbuf, sizeof(lbuf))) == NULL) {
- if (stack != 0)
- err(COMPILE, "unexpected EOF (pending }'s)");
- return (link);
- }
- semicolon: EATSPACE();
- if (*p == '#' || *p == '\0')
- continue;
- else 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");
- 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();
- if (*p == '\0')
- err(COMPILE, "filename expected");
- else
- cmd->t = duptoeol(p, "read command");
- break;
- case BRANCH: /* b t */
- p++;
- EATSPACE();
- if (*p == '\0')
- cmd->t = NULL;
- else
- cmd->t = duptoeol(p, "branch");
- break;
- case LABEL: /* : */
- p++;
- EATSPACE();
- cmd->t = duptoeol(p, "label");
- if (strlen(p) == 0)
- err(COMPILE, "empty label");
- enterlabel(cmd);
- 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 **)(void *)&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 delimiter 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] == 't') {
- *d++ = '\t';
- 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++;
- return (*s == ']') ? *sp = ++s, ++t : 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[_POSIX2_LINE_MAX + 1];
- p = compile_delimited(p, re);
- if (p && strlen(re) == 0) {
- *repp = NULL;
- return (p);
- }
- *repp = xmalloc(sizeof(regex_t));
- if (p && (eval = regcomp(*repp, re, ere)) != 0)
- err(COMPILE, "RE error: %s", strregerror(eval, *repp));
- if (maxnsub < (*repp)->re_nsub)
- maxnsub = (*repp)->re_nsub;
- 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[_POSIX2_LINE_MAX + 1];
- 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;
- asize = 2 * _POSIX2_LINE_MAX + 1;
- text = xmalloc(asize);
- size = 0;
- do {
- 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;
- if (asize - size < _POSIX2_LINE_MAX + 1) {
- asize *= 2;
- text = xrealloc(text, asize);
- }
- } while (cu_fgets(p = lbuf, sizeof(lbuf)));
- err(COMPILE, "unterminated substitute in regular expression");
- /* NOTREACHED */
- return (NULL);
- }
- /*
- * 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 */
- char wfile[_POSIX2_LINE_MAX + 1], *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;
- /* XXX Check for overflow */
- s->n = (int)strtol(p, &p, 10);
- p--;
- break;
- 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[_POSIX2_LINE_MAX + 1];
- char new[_POSIX2_LINE_MAX + 1];
- if (*p == '\0' || *p == '\\')
- err(COMPILE,
- "transform pattern can not be delimited by newline or backslash");
- p = compile_delimited(p, old);
- if (p == NULL) {
- err(COMPILE, "unterminated transform source string");
- return (NULL);
- }
- p = compile_delimited(--p, new);
- if (p == NULL) {
- err(COMPILE, "unterminated transform target string");
- return (NULL);
- }
- EATSPACE();
- if (strlen(new) != strlen(old)) {
- err(COMPILE, "transform strings are not the same length");
- return (NULL);
- }
- /* 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;
- return (p);
- }
- /*
- * Compile the text following an a, c, or i command.
- */
- static char *
- compile_text(void)
- {
- int asize, size;
- char *text, *p, *op, *s;
- char lbuf[_POSIX2_LINE_MAX + 1];
- asize = 2 * _POSIX2_LINE_MAX + 1;
- text = xmalloc(asize);
- size = 0;
- while (cu_fgets(lbuf, sizeof(lbuf))) {
- op = s = text + size;
- p = lbuf;
- for (; *p; p++) {
- if (*p == '\\')
- p++;
- *s++ = *p;
- }
- size += s - op;
- if (p[-2] != '\\') {
- *s = '\0';
- break;
- }
- if (asize - size < _POSIX2_LINE_MAX + 1) {
- asize *= 2;
- text = xrealloc(text, asize);
- }
- }
- 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 = strtol(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)
- {
- size_t len;
- int ws;
- char *start;
- ws = 0;
- for (start = s; *s != '\0' && *s != '\n'; ++s)
- ws = isspace((unsigned char)*s);
- *s = '\0';
- if (ws)
- err(WARNING, "whitespace after %s", ctype);
- len = s - start + 1;
- return (memmove(xmalloc(len), start, len));
- }
- /*
- * 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);
- }
- }
- }