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-rw-r--r--src/util/dict_regexp.c874
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diff --git a/src/util/dict_regexp.c b/src/util/dict_regexp.c
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+/*++
+/* NAME
+/* dict_regexp 3
+/* SUMMARY
+/* dictionary manager interface to REGEXP regular expression library
+/* SYNOPSIS
+/* #include <dict_regexp.h>
+/*
+/* DICT *dict_regexp_open(name, dummy, dict_flags)
+/* const char *name;
+/* int dummy;
+/* int dict_flags;
+/* DESCRIPTION
+/* dict_regexp_open() opens the named file and compiles the contained
+/* regular expressions. The result object can be used to match strings
+/* against the table.
+/* SEE ALSO
+/* dict(3) generic dictionary manager
+/* regexp_table(5) format of Postfix regular expression tables
+/* AUTHOR(S)
+/* LaMont Jones
+/* lamont@hp.com
+/*
+/* Based on PCRE dictionary contributed by Andrew McNamara
+/* andrewm@connect.com.au
+/* connect.com.au Pty. Ltd.
+/* Level 3, 213 Miller St
+/* North Sydney, NSW, Australia
+/*
+/* Heavily rewritten by Wietse Venema
+/* IBM T.J. Watson Research
+/* P.O. Box 704
+/* Yorktown Heights, NY 10598, USA
+/*
+/* Wietse Venema
+/* Google, Inc.
+/* 111 8th Avenue
+/* New York, NY 10011, USA
+/*--*/
+
+/* System library. */
+
+#include "sys_defs.h"
+
+#ifdef HAS_POSIX_REGEXP
+
+#include <sys/stat.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <ctype.h>
+#include <regex.h>
+#ifdef STRCASECMP_IN_STRINGS_H
+#include <strings.h>
+#endif
+
+/* Utility library. */
+
+#include "mymalloc.h"
+#include "msg.h"
+#include "safe.h"
+#include "vstream.h"
+#include "vstring.h"
+#include "stringops.h"
+#include "readlline.h"
+#include "dict.h"
+#include "dict_regexp.h"
+#include "mac_parse.h"
+#include "warn_stat.h"
+#include "mvect.h"
+
+ /*
+ * Support for IF/ENDIF based on an idea by Bert Driehuis.
+ */
+#define DICT_REGEXP_OP_MATCH 1 /* Match this regexp */
+#define DICT_REGEXP_OP_IF 2 /* Increase if/endif nesting on match */
+#define DICT_REGEXP_OP_ENDIF 3 /* Decrease if/endif nesting on match */
+
+ /*
+ * Regular expression before compiling.
+ */
+typedef struct {
+ char *regexp; /* regular expression */
+ int options; /* regcomp() options */
+ int match; /* positive or negative match */
+} DICT_REGEXP_PATTERN;
+
+ /*
+ * Compiled generic rule, and subclasses that derive from it.
+ */
+typedef struct DICT_REGEXP_RULE {
+ int op; /* DICT_REGEXP_OP_MATCH/IF/ENDIF */
+ int lineno; /* source file line number */
+ struct DICT_REGEXP_RULE *next; /* next rule in dict */
+} DICT_REGEXP_RULE;
+
+typedef struct {
+ DICT_REGEXP_RULE rule; /* generic part */
+ regex_t *first_exp; /* compiled primary pattern */
+ int first_match; /* positive or negative match */
+ regex_t *second_exp; /* compiled secondary pattern */
+ int second_match; /* positive or negative match */
+ char *replacement; /* replacement text */
+ size_t max_sub; /* largest $number in replacement */
+} DICT_REGEXP_MATCH_RULE;
+
+typedef struct {
+ DICT_REGEXP_RULE rule; /* generic members */
+ regex_t *expr; /* the condition */
+ int match; /* positive or negative match */
+ struct DICT_REGEXP_RULE *endif_rule;/* matching endif rule */
+} DICT_REGEXP_IF_RULE;
+
+ /*
+ * Regexp map.
+ */
+typedef struct {
+ DICT dict; /* generic members */
+ regmatch_t *pmatch; /* matched substring info */
+ DICT_REGEXP_RULE *head; /* first rule */
+ VSTRING *expansion_buf; /* lookup result */
+} DICT_REGEXP;
+
+ /*
+ * Macros to make dense code more readable.
+ */
+#define NULL_SUBSTITUTIONS (0)
+#define NULL_MATCH_RESULT ((regmatch_t *) 0)
+
+ /*
+ * Context for $number expansion callback.
+ */
+typedef struct {
+ DICT_REGEXP *dict_regexp; /* the dictionary handle */
+ DICT_REGEXP_MATCH_RULE *match_rule; /* the rule we matched */
+ const char *lookup_string; /* matched text */
+} DICT_REGEXP_EXPAND_CONTEXT;
+
+ /*
+ * Context for $number pre-scan callback.
+ */
+typedef struct {
+ const char *mapname; /* name of regexp map */
+ int lineno; /* where in file */
+ size_t max_sub; /* largest $number seen */
+ char *literal; /* constant result, $$ -> $ */
+} DICT_REGEXP_PRESCAN_CONTEXT;
+
+ /*
+ * Compatibility.
+ */
+#ifndef MAC_PARSE_OK
+#define MAC_PARSE_OK 0
+#endif
+
+/* dict_regexp_expand - replace $number with substring from matched text */
+
+static int dict_regexp_expand(int type, VSTRING *buf, void *ptr)
+{
+ DICT_REGEXP_EXPAND_CONTEXT *ctxt = (DICT_REGEXP_EXPAND_CONTEXT *) ptr;
+ DICT_REGEXP_MATCH_RULE *match_rule = ctxt->match_rule;
+ DICT_REGEXP *dict_regexp = ctxt->dict_regexp;
+ regmatch_t *pmatch;
+ size_t n;
+
+ /*
+ * Replace $number by the corresponding substring from the matched text.
+ * We pre-scanned the replacement text at compile time, so any out of
+ * range $number means that something impossible has happened.
+ */
+ if (type == MAC_PARSE_VARNAME) {
+ n = atoi(vstring_str(buf));
+ if (n < 1 || n > match_rule->max_sub)
+ msg_panic("regexp map %s, line %d: out of range replacement index \"%s\"",
+ dict_regexp->dict.name, match_rule->rule.lineno,
+ vstring_str(buf));
+ pmatch = dict_regexp->pmatch + n;
+ if (pmatch->rm_so < 0 || pmatch->rm_so == pmatch->rm_eo)
+ return (MAC_PARSE_UNDEF); /* empty or not matched */
+ vstring_strncat(dict_regexp->expansion_buf,
+ ctxt->lookup_string + pmatch->rm_so,
+ pmatch->rm_eo - pmatch->rm_so);
+ return (MAC_PARSE_OK);
+ }
+
+ /*
+ * Straight text - duplicate with no substitution.
+ */
+ else {
+ vstring_strcat(dict_regexp->expansion_buf, vstring_str(buf));
+ return (MAC_PARSE_OK);
+ }
+}
+
+/* dict_regexp_regerror - report regexp compile/execute error */
+
+static void dict_regexp_regerror(const char *mapname, int lineno, int error,
+ const regex_t *expr)
+{
+ char errbuf[256];
+
+ (void) regerror(error, expr, errbuf, sizeof(errbuf));
+ msg_warn("regexp map %s, line %d: %s", mapname, lineno, errbuf);
+}
+
+ /*
+ * Inlined to reduce function call overhead in the time-critical loop.
+ */
+#define DICT_REGEXP_REGEXEC(err, map, line, expr, match, str, nsub, pmatch) \
+ ((err) = regexec((expr), (str), (nsub), (pmatch), 0), \
+ ((err) == REG_NOMATCH ? !(match) : \
+ (err) == 0 ? (match) : \
+ (dict_regexp_regerror((map), (line), (err), (expr)), 0)))
+
+/* dict_regexp_lookup - match string and perform optional substitution */
+
+static const char *dict_regexp_lookup(DICT *dict, const char *lookup_string)
+{
+ DICT_REGEXP *dict_regexp = (DICT_REGEXP *) dict;
+ DICT_REGEXP_RULE *rule;
+ DICT_REGEXP_IF_RULE *if_rule;
+ DICT_REGEXP_MATCH_RULE *match_rule;
+ DICT_REGEXP_EXPAND_CONTEXT expand_context;
+ int error;
+
+ dict->error = 0;
+
+ if (msg_verbose)
+ msg_info("dict_regexp_lookup: %s: %s", dict->name, lookup_string);
+
+ /*
+ * Optionally fold the key.
+ */
+ if (dict->flags & DICT_FLAG_FOLD_MUL) {
+ if (dict->fold_buf == 0)
+ dict->fold_buf = vstring_alloc(10);
+ vstring_strcpy(dict->fold_buf, lookup_string);
+ lookup_string = lowercase(vstring_str(dict->fold_buf));
+ }
+ for (rule = dict_regexp->head; rule; rule = rule->next) {
+
+ switch (rule->op) {
+
+ /*
+ * Search for the first matching primary expression. Limit the
+ * overhead for substring substitution to the bare minimum.
+ */
+ case DICT_REGEXP_OP_MATCH:
+ match_rule = (DICT_REGEXP_MATCH_RULE *) rule;
+ if (!DICT_REGEXP_REGEXEC(error, dict->name, rule->lineno,
+ match_rule->first_exp,
+ match_rule->first_match,
+ lookup_string,
+ match_rule->max_sub > 0 ?
+ match_rule->max_sub + 1 : 0,
+ dict_regexp->pmatch))
+ continue;
+ if (match_rule->second_exp
+ && !DICT_REGEXP_REGEXEC(error, dict->name, rule->lineno,
+ match_rule->second_exp,
+ match_rule->second_match,
+ lookup_string,
+ NULL_SUBSTITUTIONS,
+ NULL_MATCH_RESULT))
+ continue;
+
+ /*
+ * Skip $number substitutions when the replacement text contains
+ * no $number strings, as learned during the compile time
+ * pre-scan. The pre-scan already replaced $$ by $.
+ */
+ if (match_rule->max_sub == 0)
+ return (match_rule->replacement);
+
+ /*
+ * Perform $number substitutions on the replacement text. We
+ * pre-scanned the replacement text at compile time. Any macro
+ * expansion errors at this point mean something impossible has
+ * happened.
+ */
+ if (!dict_regexp->expansion_buf)
+ dict_regexp->expansion_buf = vstring_alloc(10);
+ VSTRING_RESET(dict_regexp->expansion_buf);
+ expand_context.lookup_string = lookup_string;
+ expand_context.match_rule = match_rule;
+ expand_context.dict_regexp = dict_regexp;
+
+ if (mac_parse(match_rule->replacement, dict_regexp_expand,
+ (void *) &expand_context) & MAC_PARSE_ERROR)
+ msg_panic("regexp map %s, line %d: bad replacement syntax",
+ dict->name, rule->lineno);
+ VSTRING_TERMINATE(dict_regexp->expansion_buf);
+ return (vstring_str(dict_regexp->expansion_buf));
+
+ /*
+ * Conditional.
+ */
+ case DICT_REGEXP_OP_IF:
+ if_rule = (DICT_REGEXP_IF_RULE *) rule;
+ if (DICT_REGEXP_REGEXEC(error, dict->name, rule->lineno,
+ if_rule->expr, if_rule->match, lookup_string,
+ NULL_SUBSTITUTIONS, NULL_MATCH_RESULT))
+ continue;
+ /* An IF without matching ENDIF has no "endif" rule. */
+ if ((rule = if_rule->endif_rule) == 0)
+ return (0);
+ /* FALLTHROUGH */
+
+ /*
+ * ENDIF after IF.
+ */
+ case DICT_REGEXP_OP_ENDIF:
+ continue;
+
+ default:
+ msg_panic("dict_regexp_lookup: impossible operation %d", rule->op);
+ }
+ }
+ return (0);
+}
+
+/* dict_regexp_close - close regexp dictionary */
+
+static void dict_regexp_close(DICT *dict)
+{
+ DICT_REGEXP *dict_regexp = (DICT_REGEXP *) dict;
+ DICT_REGEXP_RULE *rule;
+ DICT_REGEXP_RULE *next;
+ DICT_REGEXP_MATCH_RULE *match_rule;
+ DICT_REGEXP_IF_RULE *if_rule;
+
+ for (rule = dict_regexp->head; rule; rule = next) {
+ next = rule->next;
+ switch (rule->op) {
+ case DICT_REGEXP_OP_MATCH:
+ match_rule = (DICT_REGEXP_MATCH_RULE *) rule;
+ if (match_rule->first_exp) {
+ regfree(match_rule->first_exp);
+ myfree((void *) match_rule->first_exp);
+ }
+ if (match_rule->second_exp) {
+ regfree(match_rule->second_exp);
+ myfree((void *) match_rule->second_exp);
+ }
+ if (match_rule->replacement)
+ myfree((void *) match_rule->replacement);
+ break;
+ case DICT_REGEXP_OP_IF:
+ if_rule = (DICT_REGEXP_IF_RULE *) rule;
+ if (if_rule->expr) {
+ regfree(if_rule->expr);
+ myfree((void *) if_rule->expr);
+ }
+ break;
+ case DICT_REGEXP_OP_ENDIF:
+ break;
+ default:
+ msg_panic("dict_regexp_close: unknown operation %d", rule->op);
+ }
+ myfree((void *) rule);
+ }
+ if (dict_regexp->pmatch)
+ myfree((void *) dict_regexp->pmatch);
+ if (dict_regexp->expansion_buf)
+ vstring_free(dict_regexp->expansion_buf);
+ if (dict->fold_buf)
+ vstring_free(dict->fold_buf);
+ dict_free(dict);
+}
+
+/* dict_regexp_get_pat - extract one pattern with options from rule */
+
+static int dict_regexp_get_pat(const char *mapname, int lineno, char **bufp,
+ DICT_REGEXP_PATTERN *pat)
+{
+ char *p = *bufp;
+ char re_delim;
+
+ /*
+ * Process negation operators.
+ */
+ pat->match = 1;
+ for (;;) {
+ if (*p == '!')
+ pat->match = !pat->match;
+ else if (!ISSPACE(*p))
+ break;
+ p++;
+ }
+ if (*p == 0) {
+ msg_warn("regexp map %s, line %d: no regexp: skipping this rule",
+ mapname, lineno);
+ return (0);
+ }
+
+ /*
+ * Search for the closing delimiter, handling backslash escape.
+ */
+ re_delim = *p++;
+ pat->regexp = p;
+ while (*p) {
+ if (*p == '\\') {
+ if (p[1])
+ p++;
+ else
+ break;
+ } else if (*p == re_delim) {
+ break;
+ }
+ ++p;
+ }
+ if (!*p) {
+ msg_warn("regexp map %s, line %d: no closing regexp delimiter \"%c\": "
+ "skipping this rule", mapname, lineno, re_delim);
+ return (0);
+ }
+ *p++ = 0; /* null terminate */
+
+ /*
+ * Search for options.
+ */
+ pat->options = REG_EXTENDED | REG_ICASE;
+ while (*p && !ISSPACE(*p) && *p != '!') {
+ switch (*p) {
+ case 'i':
+ pat->options ^= REG_ICASE;
+ break;
+ case 'm':
+ pat->options ^= REG_NEWLINE;
+ break;
+ case 'x':
+ pat->options ^= REG_EXTENDED;
+ break;
+ default:
+ msg_warn("regexp map %s, line %d: unknown regexp option \"%c\": "
+ "skipping this rule", mapname, lineno, *p);
+ return (0);
+ }
+ ++p;
+ }
+ *bufp = p;
+ return (1);
+}
+
+/* dict_regexp_get_pats - get the primary and second patterns and flags */
+
+static int dict_regexp_get_pats(const char *mapname, int lineno, char **p,
+ DICT_REGEXP_PATTERN *first_pat,
+ DICT_REGEXP_PATTERN *second_pat)
+{
+
+ /*
+ * Get the primary and optional secondary patterns and their flags.
+ */
+ if (dict_regexp_get_pat(mapname, lineno, p, first_pat) == 0)
+ return (0);
+ if (**p == '!') {
+#if 0
+ static int bitrot_warned = 0;
+
+ if (bitrot_warned == 0) {
+ msg_warn("regexp file %s, line %d: /pattern1/!/pattern2/ goes away,"
+ " use \"if !/pattern2/ ... /pattern1/ ... endif\" instead",
+ mapname, lineno);
+ bitrot_warned = 1;
+ }
+#endif
+ if (dict_regexp_get_pat(mapname, lineno, p, second_pat) == 0)
+ return (0);
+ } else {
+ second_pat->regexp = 0;
+ }
+ return (1);
+}
+
+/* dict_regexp_prescan - find largest $number in replacement text */
+
+static int dict_regexp_prescan(int type, VSTRING *buf, void *context)
+{
+ DICT_REGEXP_PRESCAN_CONTEXT *ctxt = (DICT_REGEXP_PRESCAN_CONTEXT *) context;
+ size_t n;
+
+ /*
+ * Keep a copy of literal text (with $$ already replaced by $) if and
+ * only if the replacement text contains no $number expression. This way
+ * we can avoid having to scan the replacement text at lookup time.
+ */
+ if (type == MAC_PARSE_VARNAME) {
+ if (ctxt->literal) {
+ myfree(ctxt->literal);
+ ctxt->literal = 0;
+ }
+ if (!alldig(vstring_str(buf))) {
+ msg_warn("regexp map %s, line %d: non-numeric replacement index \"%s\"",
+ ctxt->mapname, ctxt->lineno, vstring_str(buf));
+ return (MAC_PARSE_ERROR);
+ }
+ n = atoi(vstring_str(buf));
+ if (n < 1) {
+ msg_warn("regexp map %s, line %d: out-of-range replacement index \"%s\"",
+ ctxt->mapname, ctxt->lineno, vstring_str(buf));
+ return (MAC_PARSE_ERROR);
+ }
+ if (n > ctxt->max_sub)
+ ctxt->max_sub = n;
+ } else if (type == MAC_PARSE_LITERAL && ctxt->max_sub == 0) {
+ if (ctxt->literal)
+ msg_panic("regexp map %s, line %d: multiple literals but no $number",
+ ctxt->mapname, ctxt->lineno);
+ ctxt->literal = mystrdup(vstring_str(buf));
+ }
+ return (MAC_PARSE_OK);
+}
+
+/* dict_regexp_compile_pat - compile one pattern */
+
+static regex_t *dict_regexp_compile_pat(const char *mapname, int lineno,
+ DICT_REGEXP_PATTERN *pat)
+{
+ int error;
+ regex_t *expr;
+
+ expr = (regex_t *) mymalloc(sizeof(*expr));
+ error = regcomp(expr, pat->regexp, pat->options);
+ if (error != 0) {
+ dict_regexp_regerror(mapname, lineno, error, expr);
+ myfree((void *) expr);
+ return (0);
+ }
+ return (expr);
+}
+
+/* dict_regexp_rule_alloc - fill in a generic rule structure */
+
+static DICT_REGEXP_RULE *dict_regexp_rule_alloc(int op, int lineno, size_t size)
+{
+ DICT_REGEXP_RULE *rule;
+
+ rule = (DICT_REGEXP_RULE *) mymalloc(size);
+ rule->op = op;
+ rule->lineno = lineno;
+ rule->next = 0;
+
+ return (rule);
+}
+
+/* dict_regexp_parseline - parse one rule */
+
+static DICT_REGEXP_RULE *dict_regexp_parseline(DICT *dict, const char *mapname,
+ int lineno, char *line,
+ int nesting)
+{
+ char *p;
+
+ p = line;
+
+ /*
+ * An ordinary rule takes one or two patterns and replacement text.
+ */
+ if (!ISALNUM(*p)) {
+ DICT_REGEXP_PATTERN first_pat;
+ DICT_REGEXP_PATTERN second_pat;
+ DICT_REGEXP_PRESCAN_CONTEXT prescan_context;
+ regex_t *first_exp = 0;
+ regex_t *second_exp;
+ DICT_REGEXP_MATCH_RULE *match_rule;
+
+ /*
+ * Get the primary and the optional secondary patterns.
+ */
+ if (!dict_regexp_get_pats(mapname, lineno, &p, &first_pat, &second_pat))
+ return (0);
+
+ /*
+ * Get the replacement text.
+ */
+ while (*p && ISSPACE(*p))
+ ++p;
+ if (!*p) {
+ msg_warn("regexp map %s, line %d: no replacement text: "
+ "using empty string", mapname, lineno);
+ }
+
+ /*
+ * Find the highest-numbered $number in the replacement text. We can
+ * speed up pattern matching 1) by passing hints to the regexp
+ * compiler, setting the REG_NOSUB flag when the replacement text
+ * contains no $number string; 2) by passing hints to the regexp
+ * execution code, limiting the amount of text that is made available
+ * for substitution.
+ */
+ prescan_context.mapname = mapname;
+ prescan_context.lineno = lineno;
+ prescan_context.max_sub = 0;
+ prescan_context.literal = 0;
+
+ /*
+ * The optimizer will eliminate code duplication and/or dead code.
+ */
+#define CREATE_MATCHOP_ERROR_RETURN(rval) do { \
+ if (first_exp) { \
+ regfree(first_exp); \
+ myfree((void *) first_exp); \
+ } \
+ if (prescan_context.literal) \
+ myfree(prescan_context.literal); \
+ return (rval); \
+ } while (0)
+
+ if (dict->flags & DICT_FLAG_SRC_RHS_IS_FILE) {
+ VSTRING *base64_buf;
+ char *err;
+
+ if ((base64_buf = dict_file_to_b64(dict, p)) == 0) {
+ err = dict_file_get_error(dict);
+ msg_warn("regexp map %s, line %d: %s: skipping this rule",
+ mapname, lineno, err);
+ myfree(err);
+ CREATE_MATCHOP_ERROR_RETURN(0);
+ }
+ p = vstring_str(base64_buf);
+ }
+ if (mac_parse(p, dict_regexp_prescan, (void *) &prescan_context)
+ & MAC_PARSE_ERROR) {
+ msg_warn("regexp map %s, line %d: bad replacement syntax: "
+ "skipping this rule", mapname, lineno);
+ CREATE_MATCHOP_ERROR_RETURN(0);
+ }
+
+ /*
+ * Compile the primary and the optional secondary pattern. Speed up
+ * execution when no matched text needs to be substituted into the
+ * result string, or when the highest numbered substring is less than
+ * the total number of () subpatterns.
+ */
+ if (prescan_context.max_sub == 0)
+ first_pat.options |= REG_NOSUB;
+ if (prescan_context.max_sub > 0 && first_pat.match == 0) {
+ msg_warn("regexp map %s, line %d: $number found in negative match "
+ "replacement text: skipping this rule", mapname, lineno);
+ CREATE_MATCHOP_ERROR_RETURN(0);
+ }
+ if (prescan_context.max_sub > 0 && (dict->flags & DICT_FLAG_NO_REGSUB)) {
+ msg_warn("regexp map %s, line %d: "
+ "regular expression substitution is not allowed: "
+ "skipping this rule", mapname, lineno);
+ CREATE_MATCHOP_ERROR_RETURN(0);
+ }
+ if ((first_exp = dict_regexp_compile_pat(mapname, lineno,
+ &first_pat)) == 0)
+ CREATE_MATCHOP_ERROR_RETURN(0);
+ if (prescan_context.max_sub > first_exp->re_nsub) {
+ msg_warn("regexp map %s, line %d: out of range replacement index \"%d\": "
+ "skipping this rule", mapname, lineno,
+ (int) prescan_context.max_sub);
+ CREATE_MATCHOP_ERROR_RETURN(0);
+ }
+ if (second_pat.regexp != 0) {
+ second_pat.options |= REG_NOSUB;
+ if ((second_exp = dict_regexp_compile_pat(mapname, lineno,
+ &second_pat)) == 0)
+ CREATE_MATCHOP_ERROR_RETURN(0);
+ } else {
+ second_exp = 0;
+ }
+ match_rule = (DICT_REGEXP_MATCH_RULE *)
+ dict_regexp_rule_alloc(DICT_REGEXP_OP_MATCH, lineno,
+ sizeof(DICT_REGEXP_MATCH_RULE));
+ match_rule->first_exp = first_exp;
+ match_rule->first_match = first_pat.match;
+ match_rule->max_sub = prescan_context.max_sub;
+ match_rule->second_exp = second_exp;
+ match_rule->second_match = second_pat.match;
+ if (prescan_context.literal)
+ match_rule->replacement = prescan_context.literal;
+ else
+ match_rule->replacement = mystrdup(p);
+ return ((DICT_REGEXP_RULE *) match_rule);
+ }
+
+ /*
+ * The IF operator takes one pattern but no replacement text.
+ */
+ else if (strncasecmp(p, "IF", 2) == 0 && !ISALNUM(p[2])) {
+ DICT_REGEXP_PATTERN pattern;
+ regex_t *expr;
+ DICT_REGEXP_IF_RULE *if_rule;
+
+ p += 2;
+ while (*p && ISSPACE(*p))
+ p++;
+ if (!dict_regexp_get_pat(mapname, lineno, &p, &pattern))
+ return (0);
+ while (*p && ISSPACE(*p))
+ ++p;
+ if (*p) {
+ msg_warn("regexp map %s, line %d: ignoring extra text after"
+ " IF statement: \"%s\"", mapname, lineno, p);
+ msg_warn("regexp map %s, line %d: do not prepend whitespace"
+ " to statements between IF and ENDIF", mapname, lineno);
+ }
+ if ((expr = dict_regexp_compile_pat(mapname, lineno, &pattern)) == 0)
+ return (0);
+ if_rule = (DICT_REGEXP_IF_RULE *)
+ dict_regexp_rule_alloc(DICT_REGEXP_OP_IF, lineno,
+ sizeof(DICT_REGEXP_IF_RULE));
+ if_rule->expr = expr;
+ if_rule->match = pattern.match;
+ if_rule->endif_rule = 0;
+ return ((DICT_REGEXP_RULE *) if_rule);
+ }
+
+ /*
+ * The ENDIF operator takes no patterns and no replacement text.
+ */
+ else if (strncasecmp(p, "ENDIF", 5) == 0 && !ISALNUM(p[5])) {
+ DICT_REGEXP_RULE *rule;
+
+ p += 5;
+ if (nesting == 0) {
+ msg_warn("regexp map %s, line %d: ignoring ENDIF without matching IF",
+ mapname, lineno);
+ return (0);
+ }
+ while (*p && ISSPACE(*p))
+ ++p;
+ if (*p)
+ msg_warn("regexp map %s, line %d: ignoring extra text after ENDIF",
+ mapname, lineno);
+ rule = dict_regexp_rule_alloc(DICT_REGEXP_OP_ENDIF, lineno,
+ sizeof(DICT_REGEXP_RULE));
+ return (rule);
+ }
+
+ /*
+ * Unrecognized input.
+ */
+ else {
+ msg_warn("regexp map %s, line %d: ignoring unrecognized request",
+ mapname, lineno);
+ return (0);
+ }
+}
+
+/* dict_regexp_open - load and compile a file containing regular expressions */
+
+DICT *dict_regexp_open(const char *mapname, int open_flags, int dict_flags)
+{
+ const char myname[] = "dict_regexp_open";
+ DICT_REGEXP *dict_regexp;
+ VSTREAM *map_fp = 0;
+ struct stat st;
+ VSTRING *why = 0;
+ VSTRING *line_buffer = 0;
+ DICT_REGEXP_RULE *rule;
+ DICT_REGEXP_RULE *last_rule = 0;
+ int lineno;
+ int last_line = 0;
+ size_t max_sub = 0;
+ int nesting = 0;
+ char *p;
+ DICT_REGEXP_RULE **rule_stack = 0;
+ MVECT mvect;
+
+ /*
+ * Let the optimizer worry about eliminating redundant code.
+ */
+#define DICT_REGEXP_OPEN_RETURN(d) do { \
+ DICT *__d = (d); \
+ if (line_buffer != 0) \
+ vstring_free(line_buffer); \
+ if (map_fp != 0) \
+ vstream_fclose(map_fp); \
+ if (why != 0) \
+ vstring_free(why); \
+ return (__d); \
+ } while (0)
+
+ /*
+ * Sanity checks.
+ */
+ if (open_flags != O_RDONLY)
+ DICT_REGEXP_OPEN_RETURN(dict_surrogate(DICT_TYPE_REGEXP,
+ mapname, open_flags, dict_flags,
+ "%s:%s map requires O_RDONLY access mode",
+ DICT_TYPE_REGEXP, mapname));
+
+ /*
+ * Open the configuration file.
+ */
+ if ((map_fp = dict_stream_open(DICT_TYPE_REGEXP, mapname, O_RDONLY,
+ dict_flags, &st, &why)) == 0)
+ DICT_REGEXP_OPEN_RETURN(dict_surrogate(DICT_TYPE_REGEXP, mapname,
+ open_flags, dict_flags,
+ "%s", vstring_str(why)));
+ line_buffer = vstring_alloc(100);
+
+ dict_regexp = (DICT_REGEXP *) dict_alloc(DICT_TYPE_REGEXP, mapname,
+ sizeof(*dict_regexp));
+ dict_regexp->dict.lookup = dict_regexp_lookup;
+ dict_regexp->dict.close = dict_regexp_close;
+ dict_regexp->dict.flags = dict_flags | DICT_FLAG_PATTERN;
+ if (dict_flags & DICT_FLAG_FOLD_MUL)
+ dict_regexp->dict.fold_buf = vstring_alloc(10);
+ dict_regexp->head = 0;
+ dict_regexp->pmatch = 0;
+ dict_regexp->expansion_buf = 0;
+ dict_regexp->dict.owner.uid = st.st_uid;
+ dict_regexp->dict.owner.status = (st.st_uid != 0);
+
+ /*
+ * Parse the regexp table.
+ */
+ while (readllines(line_buffer, map_fp, &last_line, &lineno)) {
+ p = vstring_str(line_buffer);
+ trimblanks(p, 0)[0] = 0;
+ if (*p == 0)
+ continue;
+ rule = dict_regexp_parseline(&dict_regexp->dict, mapname, lineno,
+ p, nesting);
+ if (rule == 0)
+ continue;
+ if (rule->op == DICT_REGEXP_OP_MATCH) {
+ if (((DICT_REGEXP_MATCH_RULE *) rule)->max_sub > max_sub)
+ max_sub = ((DICT_REGEXP_MATCH_RULE *) rule)->max_sub;
+ } else if (rule->op == DICT_REGEXP_OP_IF) {
+ if (rule_stack == 0)
+ rule_stack = (DICT_REGEXP_RULE **) mvect_alloc(&mvect,
+ sizeof(*rule_stack), nesting + 1,
+ (MVECT_FN) 0, (MVECT_FN) 0);
+ else
+ rule_stack =
+ (DICT_REGEXP_RULE **) mvect_realloc(&mvect, nesting + 1);
+ rule_stack[nesting] = rule;
+ nesting++;
+ } else if (rule->op == DICT_REGEXP_OP_ENDIF) {
+ DICT_REGEXP_IF_RULE *if_rule;
+
+ if (nesting-- <= 0)
+ /* Already handled in dict_regexp_parseline(). */
+ msg_panic("%s: ENDIF without IF", myname);
+ if (rule_stack[nesting]->op != DICT_REGEXP_OP_IF)
+ msg_panic("%s: unexpected rule stack element type %d",
+ myname, rule_stack[nesting]->op);
+ if_rule = (DICT_REGEXP_IF_RULE *) rule_stack[nesting];
+ if_rule->endif_rule = rule;
+ }
+ if (last_rule == 0)
+ dict_regexp->head = rule;
+ else
+ last_rule->next = rule;
+ last_rule = rule;
+ }
+
+ while (nesting-- > 0)
+ msg_warn("regexp map %s, line %d: IF has no matching ENDIF",
+ mapname, rule_stack[nesting]->lineno);
+
+ if (rule_stack)
+ (void) mvect_free(&mvect);
+
+ /*
+ * Allocate space for only as many matched substrings as used in the
+ * replacement text.
+ */
+ if (max_sub > 0)
+ dict_regexp->pmatch =
+ (regmatch_t *) mymalloc(sizeof(regmatch_t) * (max_sub + 1));
+
+ dict_file_purge_buffers(&dict_regexp->dict);
+ DICT_REGEXP_OPEN_RETURN(DICT_DEBUG (&dict_regexp->dict));
+}
+
+#endif