/* Extended regular expression matching and search library, version 0.12. (Implements POSIX draft P10003.2/D11.2, except for internationalization features.) Copyright (C) 1993 Free Software Foundation, Inc. This program 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 2, or (at your option) any later version. This program 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, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* AIX requires this to be the first thing in the file. */ #if defined (_AIX) && !defined (REGEX_MALLOC) #pragma alloca #endif #define _GNU_SOURCE /* We need this for `regex.h', and perhaps for the Emacs include files. */ #include /* We used to test for `BSTRING' here, but only GCC and Emacs define `BSTRING', as far as I know, and neither of them use this code. */ #include #ifndef bcmp #define bcmp(s1, s2, n) memcmp ((s1), (s2), (n)) #endif #ifndef bcopy #define bcopy(s, d, n) memcpy ((d), (s), (n)) #endif #ifndef bzero #define bzero(s, n) memset ((s), 0, (n)) #endif #include /* Define the syntax stuff for \<, \>, etc. */ /* This must be nonzero for the wordchar and notwordchar pattern commands in re_match_2. */ #ifndef Sword #define Sword 1 #endif #ifdef SYNTAX_TABLE extern char *re_syntax_table; #else /* not SYNTAX_TABLE */ /* How many characters in the character set. */ #define CHAR_SET_SIZE 256 static char re_syntax_table[CHAR_SET_SIZE]; static void init_syntax_once () { register int c; static int done = 0; if (done) return; bzero (re_syntax_table, sizeof re_syntax_table); for (c = 'a'; c <= 'z'; c++) re_syntax_table[c] = Sword; for (c = 'A'; c <= 'Z'; c++) re_syntax_table[c] = Sword; for (c = '0'; c <= '9'; c++) re_syntax_table[c] = Sword; re_syntax_table['_'] = Sword; done = 1; } #endif /* not SYNTAX_TABLE */ #define SYNTAX(c) re_syntax_table[c] /* Get the interface, including the syntax bits. */ #include "regex.h" /* isalpha etc. are used for the character classes. */ #include #ifndef isascii #define isascii(c) 1 #endif #ifdef isblank #define ISBLANK(c) (isascii (c) && isblank (c)) #else #define ISBLANK(c) ((c) == ' ' || (c) == '\t') #endif #ifdef isgraph #define ISGRAPH(c) (isascii (c) && isgraph (c)) #else #define ISGRAPH(c) (isascii (c) && isprint (c) && !isspace (c)) #endif #define ISPRINT(c) (isascii (c) && isprint (c)) #define ISDIGIT(c) (isascii (c) && isdigit (c)) #define ISALNUM(c) (isascii (c) && isalnum (c)) #define ISALPHA(c) (isascii (c) && isalpha (c)) #define ISCNTRL(c) (isascii (c) && iscntrl (c)) #define ISLOWER(c) (isascii (c) && islower (c)) #define ISPUNCT(c) (isascii (c) && ispunct (c)) #define ISSPACE(c) (isascii (c) && isspace (c)) #define ISUPPER(c) (isascii (c) && isupper (c)) #define ISXDIGIT(c) (isascii (c) && isxdigit (c)) #ifndef NULL #define NULL 0 #endif /* We remove any previous definition of `SIGN_EXTEND_CHAR', since ours (we hope) works properly with all combinations of machines, compilers, `char' and `unsigned char' argument types. (Per Bothner suggested the basic approach.) */ #undef SIGN_EXTEND_CHAR #if __STDC__ #define SIGN_EXTEND_CHAR(c) ((signed char) (c)) #else /* not __STDC__ */ /* As in Harbison and Steele. */ #define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128) #endif /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we use `alloca' instead of `malloc'. This is because using malloc in re_search* or re_match* could cause memory leaks when C-g is used in Emacs; also, malloc is slower and causes storage fragmentation. On the other hand, malloc is more portable, and easier to debug. Because we sometimes use alloca, some routines have to be macros, not functions -- `alloca'-allocated space disappears at the end of the function it is called in. */ #ifdef REGEX_MALLOC #define REGEX_ALLOCATE malloc #define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize) #else /* not REGEX_MALLOC */ /* Emacs already defines alloca, sometimes. */ #ifndef alloca /* Make alloca work the best possible way. */ #ifdef __GNUC__ #define alloca __builtin_alloca #else /* not __GNUC__ */ #if HAVE_ALLOCA_H #include #else /* not __GNUC__ or HAVE_ALLOCA_H */ #ifndef _AIX /* Already did AIX, up at the top. */ char *alloca (); #endif /* not _AIX */ #endif /* not HAVE_ALLOCA_H */ #endif /* not __GNUC__ */ #endif /* not alloca */ #define REGEX_ALLOCATE alloca /* Assumes a `char *destination' variable. */ #define REGEX_REALLOCATE(source, osize, nsize) \ (destination = (char *) alloca (nsize), \ bcopy (source, destination, osize), \ destination) #endif /* not REGEX_MALLOC */ /* True if `size1' is non-NULL and PTR is pointing anywhere inside `string1' or just past its end. This works if PTR is NULL, which is a good thing. */ #define FIRST_STRING_P(ptr) \ (size1 && string1 <= (ptr) && (ptr) <= string1 + size1) /* (Re)Allocate N items of type T using malloc, or fail. */ #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t))) #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t))) #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t))) #define BYTEWIDTH 8 /* In bits. */ #define STREQ(s1, s2) ((strcmp (s1, s2) == 0)) #define MAX(a, b) ((a) > (b) ? (a) : (b)) #define MIN(a, b) ((a) < (b) ? (a) : (b)) typedef char boolean; #define false 0 #define true 1 /* These are the command codes that appear in compiled regular expressions. Some opcodes are followed by argument bytes. A command code can specify any interpretation whatsoever for its arguments. Zero bytes may appear in the compiled regular expression. The value of `exactn' is needed in search.c (search_buffer) in Emacs. So regex.h defines a symbol `RE_EXACTN_VALUE' to be 1; the value of `exactn' we use here must also be 1. */ typedef enum { no_op = 0, /* Followed by one byte giving n, then by n literal bytes. */ exactn = 1, /* Matches any (more or less) character. */ anychar, /* Matches any one char belonging to specified set. First following byte is number of bitmap bytes. Then come bytes for a bitmap saying which chars are in. Bits in each byte are ordered low-bit-first. A character is in the set if its bit is 1. A character too large to have a bit in the map is automatically not in the set. */ charset, /* Same parameters as charset, but match any character that is not one of those specified. */ charset_not, /* Start remembering the text that is matched, for storing in a register. Followed by one byte with the register number, in the range 0 to one less than the pattern buffer's re_nsub field. Then followed by one byte with the number of groups inner to this one. (This last has to be part of the start_memory only because we need it in the on_failure_jump of re_match_2.) */ start_memory, /* Stop remembering the text that is matched and store it in a memory register. Followed by one byte with the register number, in the range 0 to one less than `re_nsub' in the pattern buffer, and one byte with the number of inner groups, just like `start_memory'. (We need the number of inner groups here because we don't have any easy way of finding the corresponding start_memory when we're at a stop_memory.) */ stop_memory, /* Match a duplicate of something remembered. Followed by one byte containing the register number. */ duplicate, /* Fail unless at beginning of line. */ begline, /* Fail unless at end of line. */ endline, /* Succeeds if at beginning of buffer (if emacs) or at beginning of string to be matched (if not). */ begbuf, /* Analogously, for end of buffer/string. */ endbuf, /* Followed by two byte relative address to which to jump. */ jump, /* Same as jump, but marks the end of an alternative. */ jump_past_alt, /* Followed by two-byte relative address of place to resume at in case of failure. */ on_failure_jump, /* Like on_failure_jump, but pushes a placeholder instead of the current string position when executed. */ on_failure_keep_string_jump, /* Throw away latest failure point and then jump to following two-byte relative address. */ pop_failure_jump, /* Change to pop_failure_jump if know won't have to backtrack to match; otherwise change to jump. This is used to jump back to the beginning of a repeat. If what follows this jump clearly won't match what the repeat does, such that we can be sure that there is no use backtracking out of repetitions already matched, then we change it to a pop_failure_jump. Followed by two-byte address. */ maybe_pop_jump, /* Jump to following two-byte address, and push a dummy failure point. This failure point will be thrown away if an attempt is made to use it for a failure. A `+' construct makes this before the first repeat. Also used as an intermediary kind of jump when compiling an alternative. */ dummy_failure_jump, /* Push a dummy failure point and continue. Used at the end of alternatives. */ push_dummy_failure, /* Followed by two-byte relative address and two-byte number n. After matching N times, jump to the address upon failure. */ succeed_n, /* Followed by two-byte relative address, and two-byte number n. Jump to the address N times, then fail. */ jump_n, /* Set the following two-byte relative address to the subsequent two-byte number. The address *includes* the two bytes of number. */ set_number_at, wordchar, /* Matches any word-constituent character. */ notwordchar, /* Matches any char that is not a word-constituent. */ wordbeg, /* Succeeds if at word beginning. */ wordend, /* Succeeds if at word end. */ wordbound, /* Succeeds if at a word boundary. */ notwordbound /* Succeeds if not at a word boundary. */ #ifdef emacs ,before_dot, /* Succeeds if before point. */ at_dot, /* Succeeds if at point. */ after_dot, /* Succeeds if after point. */ /* Matches any character whose syntax is specified. Followed by a byte which contains a syntax code, e.g., Sword. */ syntaxspec, /* Matches any character whose syntax is not that specified. */ notsyntaxspec #endif /* emacs */ } re_opcode_t; /* Common operations on the compiled pattern. */ /* Store NUMBER in two contiguous bytes starting at DESTINATION. */ #define STORE_NUMBER(destination, number) \ do { \ (destination)[0] = (number) & 0377; \ (destination)[1] = (number) >> 8; \ } while (0) /* Same as STORE_NUMBER, except increment DESTINATION to the byte after where the number is stored. Therefore, DESTINATION must be an lvalue. */ #define STORE_NUMBER_AND_INCR(destination, number) \ do { \ STORE_NUMBER (destination, number); \ (destination) += 2; \ } while (0) /* Put into DESTINATION a number stored in two contiguous bytes starting at SOURCE. */ #define EXTRACT_NUMBER(destination, source) \ do { \ (destination) = *(source) & 0377; \ (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \ } while (0) #ifdef DEBUG static void extract_number (dest, source) int *dest; unsigned char *source; { int temp = SIGN_EXTEND_CHAR (*(source + 1)); *dest = *source & 0377; *dest += temp << 8; } #ifndef EXTRACT_MACROS /* To debug the macros. */ #undef EXTRACT_NUMBER #define EXTRACT_NUMBER(dest, src) extract_number (&dest, src) #endif /* not EXTRACT_MACROS */ #endif /* DEBUG */ /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number. SOURCE must be an lvalue. */ #define EXTRACT_NUMBER_AND_INCR(destination, source) \ do { \ EXTRACT_NUMBER (destination, source); \ (source) += 2; \ } while (0) #ifdef DEBUG static void extract_number_and_incr (destination, source) int *destination; unsigned char **source; { extract_number (destination, *source); *source += 2; } #ifndef EXTRACT_MACROS #undef EXTRACT_NUMBER_AND_INCR #define EXTRACT_NUMBER_AND_INCR(dest, src) \ extract_number_and_incr (&dest, &src) #endif /* not EXTRACT_MACROS */ #endif /* DEBUG */ /* If DEBUG is defined, Regex prints many voluminous messages about what it is doing (if the variable `debug' is nonzero). If linked with the main program in `iregex.c', you can enter patterns and strings interactively. And if linked with the main program in `main.c' and the other test files, you can run the already-written tests. */ #ifdef DEBUG /* We use standard I/O for debugging. */ #include /* It is useful to test things that ``must'' be true when debugging. */ #include static int debug = 0; #define DEBUG_STATEMENT(e) e #define DEBUG_PRINT1(x) if (debug) printf (x) #define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2) #define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3) #define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4) #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \ if (debug) print_partial_compiled_pattern (s, e) #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \ if (debug) print_double_string (w, s1, sz1, s2, sz2) extern void printchar (); /* Print the fastmap in human-readable form. */ void print_fastmap (fastmap) char *fastmap; { unsigned was_a_range = 0; unsigned i = 0; while (i < (1 << BYTEWIDTH)) { if (fastmap[i++]) { was_a_range = 0; printchar (i - 1); while (i < (1 << BYTEWIDTH) && fastmap[i]) { was_a_range = 1; i++; } if (was_a_range) { printf ("-"); printchar (i - 1); } } } putchar ('\n'); } /* Print a compiled pattern string in human-readable form, starting at the START pointer into it and ending just before the pointer END. */ void print_partial_compiled_pattern (start, end) unsigned char *start; unsigned char *end; { int mcnt, mcnt2; unsigned char *p = start; unsigned char *pend = end; if (start == NULL) { printf ("(null)\n"); return; } /* Loop over pattern commands. */ while (p < pend) { switch ((re_opcode_t) *p++) { case no_op: printf ("/no_op"); break; case exactn: mcnt = *p++; printf ("/exactn/%d", mcnt); do { putchar ('/'); printchar (*p++); } while (--mcnt); break; case start_memory: mcnt = *p++; printf ("/start_memory/%d/%d", mcnt, *p++); break; case stop_memory: mcnt = *p++; printf ("/stop_memory/%d/%d", mcnt, *p++); break; case duplicate: printf ("/duplicate/%d", *p++); break; case anychar: printf ("/anychar"); break; case charset: case charset_not: { register int c; printf ("/charset%s", (re_opcode_t) *(p - 1) == charset_not ? "_not" : ""); assert (p + *p < pend); for (c = 0; c < *p; c++) { unsigned bit; unsigned char map_byte = p[1 + c]; putchar ('/'); for (bit = 0; bit < BYTEWIDTH; bit++) if (map_byte & (1 << bit)) printchar (c * BYTEWIDTH + bit); } p += 1 + *p; break; } case begline: printf ("/begline"); break; case endline: printf ("/endline"); break; case on_failure_jump: extract_number_and_incr (&mcnt, &p); printf ("/on_failure_jump/0/%d", mcnt); break; case on_failure_keep_string_jump: extract_number_and_incr (&mcnt, &p); printf ("/on_failure_keep_string_jump/0/%d", mcnt); break; case dummy_failure_jump: extract_number_and_incr (&mcnt, &p); printf ("/dummy_failure_jump/0/%d", mcnt); break; case push_dummy_failure: printf ("/push_dummy_failure"); break; case maybe_pop_jump: extract_number_and_incr (&mcnt, &p); printf ("/maybe_pop_jump/0/%d", mcnt); break; case pop_failure_jump: extract_number_and_incr (&mcnt, &p); printf ("/pop_failure_jump/0/%d", mcnt); break; case jump_past_alt: extract_number_and_incr (&mcnt, &p); printf ("/jump_past_alt/0/%d", mcnt); break; case jump: extract_number_and_incr (&mcnt, &p); printf ("/jump/0/%d", mcnt); break; case succeed_n: extract_number_and_incr (&mcnt, &p); extract_number_and_incr (&mcnt2, &p); printf ("/succeed_n/0/%d/0/%d", mcnt, mcnt2); break; case jump_n: extract_number_and_incr (&mcnt, &p); extract_number_and_incr (&mcnt2, &p); printf ("/jump_n/0/%d/0/%d", mcnt, mcnt2); break; case set_number_at: extract_number_and_incr (&mcnt, &p); extract_number_and_incr (&mcnt2, &p); printf ("/set_number_at/0/%d/0/%d", mcnt, mcnt2); break; case wordbound: printf ("/wordbound"); break; case notwordbound: printf ("/notwordbound"); break; case wordbeg: printf ("/wordbeg"); break; case wordend: printf ("/wordend"); #ifdef emacs case before_dot: printf ("/before_dot"); break; case at_dot: printf ("/at_dot"); break; case after_dot: printf ("/after_dot"); break; case syntaxspec: printf ("/syntaxspec"); mcnt = *p++; printf ("/%d", mcnt); break; case notsyntaxspec: printf ("/notsyntaxspec"); mcnt = *p++; printf ("/%d", mcnt); break; #endif /* emacs */ case wordchar: printf ("/wordchar"); break; case notwordchar: printf ("/notwordchar"); break; case begbuf: printf ("/begbuf"); break; case endbuf: printf ("/endbuf"); break; default: printf ("?%d", *(p-1)); } } printf ("/\n"); } void print_compiled_pattern (bufp) struct re_pattern_buffer *bufp; { unsigned char *buffer = bufp->buffer; print_partial_compiled_pattern (buffer, buffer + bufp->used); printf ("%d bytes used/%d bytes allocated.\n", bufp->used, bufp->allocated); if (bufp->fastmap_accurate && bufp->fastmap) { printf ("fastmap: "); print_fastmap (bufp->fastmap); } printf ("re_nsub: %d\t", bufp->re_nsub); printf ("regs_alloc: %d\t", bufp->regs_allocated); printf ("can_be_null: %d\t", bufp->can_be_null); printf ("newline_anchor: %d\n", bufp->newline_anchor); printf ("no_sub: %d\t", bufp->no_sub); printf ("not_bol: %d\t", bufp->not_bol); printf ("not_eol: %d\t", bufp->not_eol); printf ("syntax: %d\n", bufp->syntax); /* Perhaps we should print the translate table? */ } void print_double_string (where, string1, size1, string2, size2) const char *where; const char *string1; const char *string2; int size1; int size2; { unsigned this_char; if (where == NULL) printf ("(null)"); else { if (FIRST_STRING_P (where)) { for (this_char = where - string1; this_char < size1; this_char++) printchar (string1[this_char]); where = string2; } for (this_char = where - string2; this_char < size2; this_char++) printchar (string2[this_char]); } } #else /* not DEBUG */ #undef assert #define assert(e) #define DEBUG_STATEMENT(e) #define DEBUG_PRINT1(x) #define DEBUG_PRINT2(x1, x2) #define DEBUG_PRINT3(x1, x2, x3) #define DEBUG_PRINT4(x1, x2, x3, x4) #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) #endif /* not DEBUG */ /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can also be assigned to arbitrarily: each pattern buffer stores its own syntax, so it can be changed between regex compilations. */ reg_syntax_t re_syntax_options = RE_SYNTAX_EMACS; /* Specify the precise syntax of regexps for compilation. This provides for compatibility for various utilities which historically have different, incompatible syntaxes. The argument SYNTAX is a bit mask comprised of the various bits defined in regex.h. We return the old syntax. */ reg_syntax_t re_set_syntax (syntax) reg_syntax_t syntax; { reg_syntax_t ret = re_syntax_options; re_syntax_options = syntax; return ret; } /* This table gives an error message for each of the error codes listed in regex.h. Obviously the order here has to be same as there. */ static const char *re_error_msg[] = { NULL, /* REG_NOERROR */ "No match", /* REG_NOMATCH */ "Invalid regular expression", /* REG_BADPAT */ "Invalid collation character", /* REG_ECOLLATE */ "Invalid character class name", /* REG_ECTYPE */ "Trailing backslash", /* REG_EESCAPE */ "Invalid back reference", /* REG_ESUBREG */ "Unmatched [ or [^", /* REG_EBRACK */ "Unmatched ( or \\(", /* REG_EPAREN */ "Unmatched \\{", /* REG_EBRACE */ "Invalid content of \\{\\}", /* REG_BADBR */ "Invalid range end", /* REG_ERANGE */ "Memory exhausted", /* REG_ESPACE */ "Invalid preceding regular expression", /* REG_BADRPT */ "Premature end of regular expression", /* REG_EEND */ "Regular expression too big", /* REG_ESIZE */ "Unmatched ) or \\)", /* REG_ERPAREN */ }; /* Subroutine declarations and macros for regex_compile. */ static void store_op1 (), store_op2 (); static void insert_op1 (), insert_op2 (); static boolean at_begline_loc_p (), at_endline_loc_p (); static boolean group_in_compile_stack (); static reg_errcode_t compile_range (); /* Fetch the next character in the uncompiled pattern---translating it if necessary. Also cast from a signed character in the constant string passed to us by the user to an unsigned char that we can use as an array index (in, e.g., `translate'). */ #define PATFETCH(c) \ do {if (p == pend) return REG_EEND; \ c = (unsigned char) *p++; \ if (translate) c = translate[c]; \ } while (0) /* Fetch the next character in the uncompiled pattern, with no translation. */ #define PATFETCH_RAW(c) \ do {if (p == pend) return REG_EEND; \ c = (unsigned char) *p++; \ } while (0) /* Go backwards one character in the pattern. */ #define PATUNFETCH p-- /* If `translate' is non-null, return translate[D], else just D. We cast the subscript to translate because some data is declared as `char *', to avoid warnings when a string constant is passed. But when we use a character as a subscript we must make it unsigned. */ #define TRANSLATE(d) (translate ? translate[(unsigned char) (d)] : (d)) /* Macros for outputting the compiled pattern into `buffer'. */ /* If the buffer isn't allocated when it comes in, use this. */ #define INIT_BUF_SIZE 32 /* Make sure we have at least N more bytes of space in buffer. */ #define GET_BUFFER_SPACE(n) \ while (b - bufp->buffer + (n) > bufp->allocated) \ EXTEND_BUFFER () /* Make sure we have one more byte of buffer space and then add C to it. */ #define BUF_PUSH(c) \ do { \ GET_BUFFER_SPACE (1); \ *b++ = (unsigned char) (c); \ } while (0) /* Ensure we have two more bytes of buffer space and then append C1 and C2. */ #define BUF_PUSH_2(c1, c2) \ do { \ GET_BUFFER_SPACE (2); \ *b++ = (unsigned char) (c1); \ *b++ = (unsigned char) (c2); \ } while (0) /* As with BUF_PUSH_2, except for three bytes. */ #define BUF_PUSH_3(c1, c2, c3) \ do { \ GET_BUFFER_SPACE (3); \ *b++ = (unsigned char) (c1); \ *b++ = (unsigned char) (c2); \ *b++ = (unsigned char) (c3); \ } while (0) /* Store a jump with opcode OP at LOC to location TO. We store a relative address offset by the three bytes the jump itself occupies. */ #define STORE_JUMP(op, loc, to) \ store_op1 (op, loc, (to) - (loc) - 3) /* Likewise, for a two-argument jump. */ #define STORE_JUMP2(op, loc, to, arg) \ store_op2 (op, loc, (to) - (loc) - 3, arg) /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */ #define INSERT_JUMP(op, loc, to) \ insert_op1 (op, loc, (to) - (loc) - 3, b) /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */ #define INSERT_JUMP2(op, loc, to, arg) \ insert_op2 (op, loc, (to) - (loc) - 3, arg, b) /* This is not an arbitrary limit: the arguments which represent offsets into the pattern are two bytes long. So if 2^16 bytes turns out to be too small, many things would have to change. */ #define MAX_BUF_SIZE (1L << 16) /* Extend the buffer by twice its current size via realloc and reset the pointers that pointed into the old block to point to the correct places in the new one. If extending the buffer results in it being larger than MAX_BUF_SIZE, then flag memory exhausted. */ #define EXTEND_BUFFER() \ do { \ unsigned char *old_buffer = bufp->buffer; \ if (bufp->allocated == MAX_BUF_SIZE) \ return REG_ESIZE; \ bufp->allocated <<= 1; \ if (bufp->allocated > MAX_BUF_SIZE) \ bufp->allocated = MAX_BUF_SIZE; \ bufp->buffer = (unsigned char *) realloc (bufp->buffer, bufp->allocated);\ if (bufp->buffer == NULL) \ return REG_ESPACE; \ /* If the buffer moved, move all the pointers into it. */ \ if (old_buffer != bufp->buffer) \ { \ b = (b - old_buffer) + bufp->buffer; \ begalt = (begalt - old_buffer) + bufp->buffer; \ if (fixup_alt_jump) \ fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\ if (laststart) \ laststart = (laststart - old_buffer) + bufp->buffer; \ if (pending_exact) \ pending_exact = (pending_exact - old_buffer) + bufp->buffer; \ } \ } while (0) /* Since we have one byte reserved for the register number argument to {start,stop}_memory, the maximum number of groups we can report things about is what fits in that byte. */ #define MAX_REGNUM 255 /* But patterns can have more than `MAX_REGNUM' registers. We just ignore the excess. */ typedef unsigned regnum_t; /* Macros for the compile stack. */ /* Since offsets can go either forwards or backwards, this type needs to be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */ typedef int pattern_offset_t; typedef struct { pattern_offset_t begalt_offset; pattern_offset_t fixup_alt_jump; pattern_offset_t inner_group_offset; pattern_offset_t laststart_offset; regnum_t regnum; } compile_stack_elt_t; typedef struct { compile_stack_elt_t *stack; unsigned size; unsigned avail; /* Offset of next open position. */ } compile_stack_type; #define INIT_COMPILE_STACK_SIZE 32 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0) #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size) /* The next available element. */ #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail]) /* Set the bit for character C in a list. */ #define SET_LIST_BIT(c) \ (b[((unsigned char) (c)) / BYTEWIDTH] \ |= 1 << (((unsigned char) c) % BYTEWIDTH)) /* Get the next unsigned number in the uncompiled pattern. */ #define GET_UNSIGNED_NUMBER(num) \ { if (p != pend) \ { \ PATFETCH (c); \ while (ISDIGIT (c)) \ { \ if (num < 0) \ num = 0; \ num = num * 10 + c - '0'; \ if (p == pend) \ break; \ PATFETCH (c); \ } \ } \ } #define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */ #define IS_CHAR_CLASS(string) \ (STREQ (string, "alpha") || STREQ (string, "upper") \ || STREQ (string, "lower") || STREQ (string, "digit") \ || STREQ (string, "alnum") || STREQ (string, "xdigit") \ || STREQ (string, "space") || STREQ (string, "print") \ || STREQ (string, "punct") || STREQ (string, "graph") \ || STREQ (string, "cntrl") || STREQ (string, "blank")) /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX. Returns one of error codes defined in `regex.h', or zero for success. Assumes the `allocated' (and perhaps `buffer') and `translate' fields are set in BUFP on entry. If it succeeds, results are put in BUFP (if it returns an error, the contents of BUFP are undefined): `buffer' is the compiled pattern; `syntax' is set to SYNTAX; `used' is set to the length of the compiled pattern; `fastmap_accurate' is zero; `re_nsub' is the number of subexpressions in PATTERN; `not_bol' and `not_eol' are zero; The `fastmap' and `newline_anchor' fields are neither examined nor set. */ static reg_errcode_t regex_compile (pattern, size, syntax, bufp) const char *pattern; int size; reg_syntax_t syntax; struct re_pattern_buffer *bufp; { /* We fetch characters from PATTERN here. Even though PATTERN is `char *' (i.e., signed), we declare these variables as unsigned, so they can be reliably used as array indices. */ register unsigned char c, c1; /* A random tempory spot in PATTERN. */ const char *p1; /* Points to the end of the buffer, where we should append. */ register unsigned char *b; /* Keeps track of unclosed groups. */ compile_stack_type compile_stack; /* Points to the current (ending) position in the pattern. */ const char *p = pattern; const char *pend = pattern + size; /* How to translate the characters in the pattern. */ char *translate = bufp->translate; /* Address of the count-byte of the most recently inserted `exactn' command. This makes it possible to tell if a new exact-match character can be added to that command or if the character requires a new `exactn' command. */ unsigned char *pending_exact = 0; /* Address of start of the most recently finished expression. This tells, e.g., postfix * where to find the start of its operand. Reset at the beginning of groups and alternatives. */ unsigned char *laststart = 0; /* Address of beginning of regexp, or inside of last group. */ unsigned char *begalt; /* Place in the uncompiled pattern (i.e., the {) to which to go back if the interval is invalid. */ const char *beg_interval; /* Address of the place where a forward jump should go to the end of the containing expression. Each alternative of an `or' -- except the last -- ends with a forward jump of this sort. */ unsigned char *fixup_alt_jump = 0; /* Counts open-groups as they are encountered. Remembered for the matching close-group on the compile stack, so the same register number is put in the stop_memory as the start_memory. */ regnum_t regnum = 0; #ifdef DEBUG DEBUG_PRINT1 ("\nCompiling pattern: "); if (debug) { unsigned debug_count; for (debug_count = 0; debug_count < size; debug_count++) printchar (pattern[debug_count]); putchar ('\n'); } #endif /* DEBUG */ /* Initialize the compile stack. */ compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t); if (compile_stack.stack == NULL) return REG_ESPACE; compile_stack.size = INIT_COMPILE_STACK_SIZE; compile_stack.avail = 0; /* Initialize the pattern buffer. */ bufp->syntax = syntax; bufp->fastmap_accurate = 0; bufp->not_bol = bufp->not_eol = 0; /* Set `used' to zero, so that if we return an error, the pattern printer (for debugging) will think there's no pattern. We reset it at the end. */ bufp->used = 0; /* Always count groups, whether or not bufp->no_sub is set. */ bufp->re_nsub = 0; #if !defined (emacs) && !defined (SYNTAX_TABLE) /* Initialize the syntax table. */ init_syntax_once (); #endif if (bufp->allocated == 0) { if (bufp->buffer) { /* If zero allocated, but buffer is non-null, try to realloc enough space. This loses if buffer's address is bogus, but that is the user's responsibility. */ RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char); } else { /* Caller did not allocate a buffer. Do it for them. */ bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char); } if (!bufp->buffer) return REG_ESPACE; bufp->allocated = INIT_BUF_SIZE; } begalt = b = bufp->buffer; /* Loop through the uncompiled pattern until we're at the end. */ while (p != pend) { PATFETCH (c); switch (c) { case '^': { if ( /* If at start of pattern, it's an operator. */ p == pattern + 1 /* If context independent, it's an operator. */ || syntax & RE_CONTEXT_INDEP_ANCHORS /* Otherwise, depends on what's come before. */ || at_begline_loc_p (pattern, p, syntax)) BUF_PUSH (begline); else goto normal_char; } break; case '$': { if ( /* If at end of pattern, it's an operator. */ p == pend /* If context independent, it's an operator. */ || syntax & RE_CONTEXT_INDEP_ANCHORS /* Otherwise, depends on what's next. */ || at_endline_loc_p (p, pend, syntax)) BUF_PUSH (endline); else goto normal_char; } break; case '+': case '?': if ((syntax & RE_BK_PLUS_QM) || (syntax & RE_LIMITED_OPS)) goto normal_char; handle_plus: case '*': /* If there is no previous pattern... */ if (!laststart) { if (syntax & RE_CONTEXT_INVALID_OPS) return REG_BADRPT; else if (!(syntax & RE_CONTEXT_INDEP_OPS)) goto normal_char; } { /* Are we optimizing this jump? */ boolean keep_string_p = false; /* 1 means zero (many) matches is allowed. */ char zero_times_ok = 0, many_times_ok = 0; /* If there is a sequence of repetition chars, collapse it down to just one (the right one). We can't combine interval operators with these because of, e.g., `a{2}*', which should only match an even number of `a's. */ for (;;) { zero_times_ok |= c != '+'; many_times_ok |= c != '?'; if (p == pend) break; PATFETCH (c); if (c == '*' || (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?'))) ; else if (syntax & RE_BK_PLUS_QM && c == '\\') { if (p == pend) return REG_EESCAPE; PATFETCH (c1); if (!(c1 == '+' || c1 == '?')) { PATUNFETCH; PATUNFETCH; break; } c = c1; } else { PATUNFETCH; break; } /* If we get here, we found another repeat character. */ } /* Star, etc. applied to an empty pattern is equivalent to an empty pattern. */ if (!laststart) break; /* Now we know whether or not zero matches is allowed and also whether or not two or more matches is allowed. */ if (many_times_ok) { /* More than one repetition is allowed, so put in at the end a backward relative jump from `b' to before the next jump we're going to put in below (which jumps from laststart to after this jump). But if we are at the `*' in the exact sequence `.*\n', insert an unconditional jump backwards to the ., instead of the beginning of the loop. This way we only push a failure point once, instead of every time through the loop. */ assert (p - 1 > pattern); /* Allocate the space for the jump. */ GET_BUFFER_SPACE (3); /* We know we are not at the first character of the pattern, because laststart was nonzero. And we've already incremented `p', by the way, to be the character after the `*'. Do we have to do something analogous here for null bytes, because of RE_DOT_NOT_NULL? */ if (TRANSLATE (*(p - 2)) == TRANSLATE ('.') && zero_times_ok && p < pend && TRANSLATE (*p) == TRANSLATE ('\n') && !(syntax & RE_DOT_NEWLINE)) { /* We have .*\n. */ STORE_JUMP (jump, b, laststart); keep_string_p = true; } else /* Anything else. */ STORE_JUMP (maybe_pop_jump, b, laststart - 3); /* We've added more stuff to the buffer. */ b += 3; } /* On failure, jump from laststart to b + 3, which will be the end of the buffer after this jump is inserted. */ GET_BUFFER_SPACE (3); INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump : on_failure_jump, laststart, b + 3); pending_exact = 0; b += 3; if (!zero_times_ok) { /* At least one repetition is required, so insert a `dummy_failure_jump' before the initial `on_failure_jump' instruction of the loop. This effects a skip over that instruction the first time we hit that loop. */ GET_BUFFER_SPACE (3); INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6); b += 3; } } break; case '.': laststart = b; BUF_PUSH (anychar); break; case '[': { boolean had_char_class = false; if (p == pend) return REG_EBRACK; /* Ensure that we have enough space to push a charset: the opcode, the length count, and the bitset; 34 bytes in all. */ GET_BUFFER_SPACE (34); laststart = b; /* We test `*p == '^' twice, instead of using an if statement, so we only need one BUF_PUSH. */ BUF_PUSH (*p == '^' ? charset_not : charset); if (*p == '^') p++; /* Remember the first position in the bracket expression. */ p1 = p; /* Push the number of bytes in the bitmap. */ BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH); /* Clear the whole map. */ bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH); /* charset_not matches newline according to a syntax bit. */ if ((re_opcode_t) b[-2] == charset_not && (syntax & RE_HAT_LISTS_NOT_NEWLINE)) SET_LIST_BIT ('\n'); /* Read in characters and ranges, setting map bits. */ for (;;) { if (p == pend) return REG_EBRACK; PATFETCH (c); /* \ might escape characters inside [...] and [^...]. */ if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\') { if (p == pend) return REG_EESCAPE; PATFETCH (c1); SET_LIST_BIT (c1); continue; } /* Could be the end of the bracket expression. If it's not (i.e., when the bracket expression is `[]' so far), the ']' character bit gets set way below. */ if (c == ']' && p != p1 + 1) break; /* Look ahead to see if it's a range when the last thing was a character class. */ if (had_char_class && c == '-' && *p != ']') return REG_ERANGE; /* Look ahead to see if it's a range when the last thing was a character: if this is a hyphen not at the beginning or the end of a list, then it's the range operator. */ if (c == '-' && !(p - 2 >= pattern && p[-2] == '[') && !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^') && *p != ']') { reg_errcode_t ret = compile_range (&p, pend, translate, syntax, b); if (ret != REG_NOERROR) return ret; } else if (p[0] == '-' && p[1] != ']') { /* This handles ranges made up of characters only. */ reg_errcode_t ret; /* Move past the `-'. */ PATFETCH (c1); ret = compile_range (&p, pend, translate, syntax, b); if (ret != REG_NOERROR) return ret; } /* See if we're at the beginning of a possible character class. */ else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':') { /* Leave room for the null. */ char str[CHAR_CLASS_MAX_LENGTH + 1]; PATFETCH (c); c1 = 0; /* If pattern is `[[:'. */ if (p == pend) return REG_EBRACK; for (;;) { PATFETCH (c); if (c == ':' || c == ']' || p == pend || c1 == CHAR_CLASS_MAX_LENGTH) break; str[c1++] = c; } str[c1] = '\0'; /* If isn't a word bracketed by `[:' and:`]': undo the ending character, the letters, and leave the leading `:' and `[' (but set bits for them). */ if (c == ':' && *p == ']') { int ch; boolean is_alnum = STREQ (str, "alnum"); boolean is_alpha = STREQ (str, "alpha"); boolean is_blank = STREQ (str, "blank"); boolean is_cntrl = STREQ (str, "cntrl"); boolean is_digit = STREQ (str, "digit"); boolean is_graph = STREQ (str, "graph"); boolean is_lower = STREQ (str, "lower"); boolean is_print = STREQ (str, "print"); boolean is_punct = STREQ (str, "punct"); boolean is_space = STREQ (str, "space"); boolean is_upper = STREQ (str, "upper"); boolean is_xdigit = STREQ (str, "xdigit"); if (!IS_CHAR_CLASS (str)) return REG_ECTYPE; /* Throw away the ] at the end of the character class. */ PATFETCH (c); if (p == pend) return REG_EBRACK; for (ch = 0; ch < 1 << BYTEWIDTH; ch++) { if ( (is_alnum && ISALNUM (ch)) || (is_alpha && ISALPHA (ch)) || (is_blank && ISBLANK (ch)) || (is_cntrl && ISCNTRL (ch)) || (is_digit && ISDIGIT (ch)) || (is_graph && ISGRAPH (ch)) || (is_lower && ISLOWER (ch)) || (is_print && ISPRINT (ch)) || (is_punct && ISPUNCT (ch)) || (is_space && ISSPACE (ch)) || (is_upper && ISUPPER (ch)) || (is_xdigit && ISXDIGIT (ch))) SET_LIST_BIT (ch); } had_char_class = true; } else { c1++; while (c1--) PATUNFETCH; SET_LIST_BIT ('['); SET_LIST_BIT (':'); had_char_class = false; } } else { had_char_class = false; SET_LIST_BIT (c); } } /* Discard any (non)matching list bytes that are all 0 at the end of the map. Decrease the map-length byte too. */ while ((int) b[-1] > 0 && b[b[-1] - 1] == 0) b[-1]--; b += b[-1]; } break; case '(': if (syntax & RE_NO_BK_PARENS) goto handle_open; else goto normal_char; case ')': if (syntax & RE_NO_BK_PARENS) goto handle_close; else goto normal_char; case '\n': if (syntax & RE_NEWLINE_ALT) goto handle_alt; else goto normal_char; case '|': if (syntax & RE_NO_BK_VBAR) goto handle_alt; else goto normal_char; case '{': if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES) goto handle_interval; else goto normal_char; case '\\': if (p == pend) return REG_EESCAPE; /* Do not translate the character after the \, so that we can distinguish, e.g., \B from \b, even if we normally would translate, e.g., B to b. */ PATFETCH_RAW (c); switch (c) { case '(': if (syntax & RE_NO_BK_PARENS) goto normal_backslash; handle_open: bufp->re_nsub++; regnum++; if (COMPILE_STACK_FULL) { RETALLOC (compile_stack.stack, compile_stack.size << 1, compile_stack_elt_t); if (compile_stack.stack == NULL) return REG_ESPACE; compile_stack.size <<= 1; } /* These are the values to restore when we hit end of this group. They are all relative offsets, so that if the whole pattern moves because of realloc, they will still be valid. */ COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer; COMPILE_STACK_TOP.fixup_alt_jump = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0; COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer; COMPILE_STACK_TOP.regnum = regnum; /* We will eventually replace the 0 with the number of groups inner to this one. But do not push a start_memory for groups beyond the last one we can represent in the compiled pattern. */ if (regnum <= MAX_REGNUM) { COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2; BUF_PUSH_3 (start_memory, regnum, 0); } compile_stack.avail++; fixup_alt_jump = 0; laststart = 0; begalt = b; /* If we've reached MAX_REGNUM groups, then this open won't actually generate any code, so we'll have to clear pending_exact explicitly. */ pending_exact = 0; break; case ')': if (syntax & RE_NO_BK_PARENS) goto normal_backslash; if (COMPILE_STACK_EMPTY) { if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD) goto normal_backslash; else return REG_ERPAREN; } handle_close: if (fixup_alt_jump) { /* Push a dummy failure point at the end of the alternative for a possible future `pop_failure_jump' to pop. See comments at `push_dummy_failure' in `re_match_2'. */ BUF_PUSH (push_dummy_failure); /* We allocated space for this jump when we assigned to `fixup_alt_jump', in the `handle_alt' case below. */ STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1); } /* See similar code for backslashed left paren above. */ if (COMPILE_STACK_EMPTY) { if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD) goto normal_char; else return REG_ERPAREN; } /* Since we just checked for an empty stack above, this ``can't happen''. */ assert (compile_stack.avail != 0); { /* We don't just want to restore into `regnum', because later groups should continue to be numbered higher, as in `(ab)c(de)' -- the second group is #2. */ regnum_t this_group_regnum; compile_stack.avail--; begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset; fixup_alt_jump = COMPILE_STACK_TOP.fixup_alt_jump ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1 : 0; laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset; this_group_regnum = COMPILE_STACK_TOP.regnum; /* If we've reached MAX_REGNUM groups, then this open won't actually generate any code, so we'll have to clear pending_exact explicitly. */ pending_exact = 0; /* We're at the end of the group, so now we know how many groups were inside this one. */ if (this_group_regnum <= MAX_REGNUM) { unsigned char *inner_group_loc = bufp->buffer + COMPILE_STACK_TOP.inner_group_offset; *inner_group_loc = regnum - this_group_regnum; BUF_PUSH_3 (stop_memory, this_group_regnum, regnum - this_group_regnum); } } break; case '|': /* `\|'. */ if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR) goto normal_backslash; handle_alt: if (syntax & RE_LIMITED_OPS) goto normal_char; /* Insert before the previous alternative a jump which jumps to this alternative if the former fails. */ GET_BUFFER_SPACE (3); INSERT_JUMP (on_failure_jump, begalt, b + 6); pending_exact = 0; b += 3; /* The alternative before this one has a jump after it which gets executed if it gets matched. Adjust that jump so it will jump to this alternative's analogous jump (put in below, which in turn will jump to the next (if any) alternative's such jump, etc.). The last such jump jumps to the correct final destination. A picture: _____ _____ | | | | | v | v a | b | c If we are at `b', then fixup_alt_jump right now points to a three-byte space after `a'. We'll put in the jump, set fixup_alt_jump to right after `b', and leave behind three bytes which we'll fill in when we get to after `c'. */ if (fixup_alt_jump) STORE_JUMP (jump_past_alt, fixup_alt_jump, b); /* Mark and leave space for a jump after this alternative, to be filled in later either by next alternative or when know we're at the end of a series of alternatives. */ fixup_alt_jump = b; GET_BUFFER_SPACE (3); b += 3; laststart = 0; begalt = b; break; case '{': /* If \{ is a literal. */ if (!(syntax & RE_INTERVALS) /* If we're at `\{' and it's not the open-interval operator. */ || ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES)) || (p - 2 == pattern && p == pend)) goto normal_backslash; handle_interval: { /* If got here, then the syntax allows intervals. */ /* At least (most) this many matches must be made. */ int lower_bound = -1, upper_bound = -1; beg_interval = p - 1; if (p == pend) { if (syntax & RE_NO_BK_BRACES) goto unfetch_interval; else return REG_EBRACE; } GET_UNSIGNED_NUMBER (lower_bound); if (c == ',') { GET_UNSIGNED_NUMBER (upper_bound); if (upper_bound < 0) upper_bound = RE_DUP_MAX; } else /* Interval such as `{1}' => match exactly once. */ upper_bound = lower_bound; if (lower_bound < 0 || upper_bound > RE_DUP_MAX || lower_bound > upper_bound) { if (syntax & RE_NO_BK_BRACES) goto unfetch_interval; else return REG_BADBR; } if (!(syntax & RE_NO_BK_BRACES)) { if (c != '\\') return REG_EBRACE; PATFETCH (c); } if (c != '}') { if (syntax & RE_NO_BK_BRACES) goto unfetch_interval; else return REG_BADBR; } /* We just parsed a valid interval. */ /* If it's invalid to have no preceding re. */ if (!laststart) { if (syntax & RE_CONTEXT_INVALID_OPS) return REG_BADRPT; else if (syntax & RE_CONTEXT_INDEP_OPS) laststart = b; else goto unfetch_interval; } /* If the upper bound is zero, don't want to succeed at all; jump from `laststart' to `b + 3', which will be the end of the buffer after we insert the jump. */ if (upper_bound == 0) { GET_BUFFER_SPACE (3); INSERT_JUMP (jump, laststart, b + 3); b += 3; } /* Otherwise, we have a nontrivial interval. When we're all done, the pattern will look like: set_number_at set_number_at succeed_n jump_n (The upper bound and `jump_n' are omitted if `upper_bound' is 1, though.) */ else { /* If the upper bound is > 1, we need to insert more at the end of the loop. */ unsigned nbytes = 10 + (upper_bound > 1) * 10; GET_BUFFER_SPACE (nbytes); /* Initialize lower bound of the `succeed_n', even though it will be set during matching by its attendant `set_number_at' (inserted next), because `re_compile_fastmap' needs to know. Jump to the `jump_n' we might insert below. */ INSERT_JUMP2 (succeed_n, laststart, b + 5 + (upper_bound > 1) * 5, lower_bound); b += 5; /* Code to initialize the lower bound. Insert before the `succeed_n'. The `5' is the last two bytes of this `set_number_at', plus 3 bytes of the following `succeed_n'. */ insert_op2 (set_number_at, laststart, 5, lower_bound, b); b += 5; if (upper_bound > 1) { /* More than one repetition is allowed, so append a backward jump to the `succeed_n' that starts this interval. When we've reached this during matching, we'll have matched the interval once, so jump back only `upper_bound - 1' times. */ STORE_JUMP2 (jump_n, b, laststart + 5, upper_bound - 1); b += 5; /* The location we want to set is the second parameter of the `jump_n'; that is `b-2' as an absolute address. `laststart' will be the `set_number_at' we're about to insert; `laststart+3' the number to set, the source for the relative address. But we are inserting into the middle of the pattern -- so everything is getting moved up by 5. Conclusion: (b - 2) - (laststart + 3) + 5, i.e., b - laststart. We insert this at the beginning of the loop so that if we fail during matching, we'll reinitialize the bounds. */ insert_op2 (set_number_at, laststart, b - laststart, upper_bound - 1, b); b += 5; } } pending_exact = 0; beg_interval = NULL; } break; unfetch_interval: /* If an invalid interval, match the characters as literals. */ assert (beg_interval); p = beg_interval; beg_interval = NULL; /* normal_char and normal_backslash need `c'. */ PATFETCH (c); if (!(syntax & RE_NO_BK_BRACES)) { if (p > pattern && p[-1] == '\\') goto normal_backslash; } goto normal_char; #ifdef emacs /* There is no way to specify the before_dot and after_dot operators. rms says this is ok. --karl */ case '=': BUF_PUSH (at_dot); break; case 's': laststart = b; PATFETCH (c); BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]); break; case 'S': laststart = b; PATFETCH (c); BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]); break; #endif /* emacs */ case 'w': laststart = b; BUF_PUSH (wordchar); break; case 'W': laststart = b; BUF_PUSH (notwordchar); break; case '<': BUF_PUSH (wordbeg); break; case '>': BUF_PUSH (wordend); break; case 'b': BUF_PUSH (wordbound); break; case 'B': BUF_PUSH (notwordbound); break; case '`': BUF_PUSH (begbuf); break; case '\'': BUF_PUSH (endbuf); break; case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': if (syntax & RE_NO_BK_REFS) goto normal_char; c1 = c - '0'; if (c1 > regnum) return REG_ESUBREG; /* Can't back reference to a subexpression if inside of it. */ if (group_in_compile_stack (compile_stack, c1)) goto normal_char; laststart = b; BUF_PUSH_2 (duplicate, c1); break; case '+': case '?': if (syntax & RE_BK_PLUS_QM) goto handle_plus; else goto normal_backslash; default: normal_backslash: /* You might think it would be useful for \ to mean not to translate; but if we don't translate it it will never match anything. */ c = TRANSLATE (c); goto normal_char; } break; default: /* Expects the character in `c'. */ normal_char: /* If no exactn currently being built. */ if (!pending_exact /* If last exactn not at current position. */ || pending_exact + *pending_exact + 1 != b /* We have only one byte following the exactn for the count. */ || *pending_exact == (1 << BYTEWIDTH) - 1 /* If followed by a repetition operator. */ || *p == '*' || *p == '^' || ((syntax & RE_BK_PLUS_QM) ? *p == '\\' && (p[1] == '+' || p[1] == '?') : (*p == '+' || *p == '?')) || ((syntax & RE_INTERVALS) && ((syntax & RE_NO_BK_BRACES) ? *p == '{' : (p[0] == '\\' && p[1] == '{')))) { /* Start building a new exactn. */ laststart = b; BUF_PUSH_2 (exactn, 0); pending_exact = b - 1; } BUF_PUSH (c); (*pending_exact)++; break; } /* switch (c) */ } /* while p != pend */ /* Through the pattern now. */ if (fixup_alt_jump) STORE_JUMP (jump_past_alt, fixup_alt_jump, b); if (!COMPILE_STACK_EMPTY) return REG_EPAREN; free (compile_stack.stack); /* We have succeeded; set the length of the buffer. */ bufp->used = b - bufp->buffer; #ifdef DEBUG if (debug) { DEBUG_PRINT1 ("\nCompiled pattern: "); print_compiled_pattern (bufp); } #endif /* DEBUG */ return REG_NOERROR; } /* regex_compile */ /* Subroutines for `regex_compile'. */ /* Store OP at LOC followed by two-byte integer parameter ARG. */ static void store_op1 (op, loc, arg) re_opcode_t op; unsigned char *loc; int arg; { *loc = (unsigned char) op; STORE_NUMBER (loc + 1, arg); } /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */ static void store_op2 (op, loc, arg1, arg2) re_opcode_t op; unsigned char *loc; int arg1, arg2; { *loc = (unsigned char) op; STORE_NUMBER (loc + 1, arg1); STORE_NUMBER (loc + 3, arg2); } /* Copy the bytes from LOC to END to open up three bytes of space at LOC for OP followed by two-byte integer parameter ARG. */ static void insert_op1 (op, loc, arg, end) re_opcode_t op; unsigned char *loc; int arg; unsigned char *end; { register unsigned char *pfrom = end; register unsigned char *pto = end + 3; while (pfrom != loc) *--pto = *--pfrom; store_op1 (op, loc, arg); } /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */ static void insert_op2 (op, loc, arg1, arg2, end) re_opcode_t op; unsigned char *loc; int arg1, arg2; unsigned char *end; { register unsigned char *pfrom = end; register unsigned char *pto = end + 5; while (pfrom != loc) *--pto = *--pfrom; store_op2 (op, loc, arg1, arg2); } /* P points to just after a ^ in PATTERN. Return true if that ^ comes after an alternative or a begin-subexpression. We assume there is at least one character before the ^. */ static boolean at_begline_loc_p (pattern, p, syntax) const char *pattern, *p; reg_syntax_t syntax; { const char *prev = p - 2; boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\'; return /* After a subexpression? */ (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash)) /* After an alternative? */ || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash)); } /* The dual of at_begline_loc_p. This one is for $. We assume there is at least one character after the $, i.e., `P < PEND'. */ static boolean at_endline_loc_p (p, pend, syntax) const char *p, *pend; int syntax; { const char *next = p; boolean next_backslash = *next == '\\'; const char *next_next = p + 1 < pend ? p + 1 : NULL; return /* Before a subexpression? */ (syntax & RE_NO_BK_PARENS ? *next == ')' : next_backslash && next_next && *next_next == ')') /* Before an alternative? */ || (syntax & RE_NO_BK_VBAR ? *next == '|' : next_backslash && next_next && *next_next == '|'); } /* Returns true if REGNUM is in one of COMPILE_STACK's elements and false if it's not. */ static boolean group_in_compile_stack (compile_stack, regnum) compile_stack_type compile_stack; regnum_t regnum; { int this_element; for (this_element = compile_stack.avail - 1; this_element >= 0; this_element--) if (compile_stack.stack[this_element].regnum == regnum) return true; return false; } /* Read the ending character of a range (in a bracket expression) from the uncompiled pattern *P_PTR (which ends at PEND). We assume the starting character is in `P[-2]'. (`P[-1]' is the character `-'.) Then we set the translation of all bits between the starting and ending characters (inclusive) in the compiled pattern B. Return an error code. We use these short variable names so we can use the same macros as `regex_compile' itself. */ static reg_errcode_t compile_range (p_ptr, pend, translate, syntax, b) const char **p_ptr, *pend; char *translate; reg_syntax_t syntax; unsigned char *b; { unsigned this_char; const char *p = *p_ptr; int range_start, range_end; if (p == pend) return REG_ERANGE; /* Even though the pattern is a signed `char *', we need to fetch with unsigned char *'s; if the high bit of the pattern character is set, the range endpoints will be negative if we fetch using a signed char *. We also want to fetch the endpoints without translating them; the appropriate translation is done in the bit-setting loop below. */ range_start = ((unsigned char *) p)[-2]; range_end = ((unsigned char *) p)[0]; /* Have to increment the pointer into the pattern string, so the caller isn't still at the ending character. */ (*p_ptr)++; /* If the start is after the end, the range is empty. */ if (range_start > range_end) return syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR; /* Here we see why `this_char' has to be larger than an `unsigned char' -- the range is inclusive, so if `range_end' == 0xff (assuming 8-bit characters), we would otherwise go into an infinite loop, since all characters <= 0xff. */ for (this_char = range_start; this_char <= range_end; this_char++) { SET_LIST_BIT (TRANSLATE (this_char)); } return REG_NOERROR; } /* Failure stack declarations and macros; both re_compile_fastmap and re_match_2 use a failure stack. These have to be macros because of REGEX_ALLOCATE. */ /* Number of failure points for which to initially allocate space when matching. If this number is exceeded, we allocate more space, so it is not a hard limit. */ #ifndef INIT_FAILURE_ALLOC #define INIT_FAILURE_ALLOC 5 #endif /* Roughly the maximum number of failure points on the stack. Would be exactly that if always used MAX_FAILURE_SPACE each time we failed. This is a variable only so users of regex can assign to it; we never change it ourselves. */ int re_max_failures = 2000; typedef const unsigned char *fail_stack_elt_t; typedef struct { fail_stack_elt_t *stack; unsigned size; unsigned avail; /* Offset of next open position. */ } fail_stack_type; #define FAIL_STACK_EMPTY() (fail_stack.avail == 0) #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0) #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size) #define FAIL_STACK_TOP() (fail_stack.stack[fail_stack.avail]) /* Initialize `fail_stack'. Do `return -2' if the alloc fails. */ #define INIT_FAIL_STACK() \ do { \ fail_stack.stack = (fail_stack_elt_t *) \ REGEX_ALLOCATE (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \ \ if (fail_stack.stack == NULL) \ return -2; \ \ fail_stack.size = INIT_FAILURE_ALLOC; \ fail_stack.avail = 0; \ } while (0) /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items. Return 1 if succeeds, and 0 if either ran out of memory allocating space for it or it was already too large. REGEX_REALLOCATE requires `destination' be declared. */ #define DOUBLE_FAIL_STACK(fail_stack) \ ((fail_stack).size > re_max_failures * MAX_FAILURE_ITEMS \ ? 0 \ : ((fail_stack).stack = (fail_stack_elt_t *) \ REGEX_REALLOCATE ((fail_stack).stack, \ (fail_stack).size * sizeof (fail_stack_elt_t), \ ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \ \ (fail_stack).stack == NULL \ ? 0 \ : ((fail_stack).size <<= 1, \ 1))) /* Push PATTERN_OP on FAIL_STACK. Return 1 if was able to do so and 0 if ran out of memory allocating space to do so. */ #define PUSH_PATTERN_OP(pattern_op, fail_stack) \ ((FAIL_STACK_FULL () \ && !DOUBLE_FAIL_STACK (fail_stack)) \ ? 0 \ : ((fail_stack).stack[(fail_stack).avail++] = pattern_op, \ 1)) /* This pushes an item onto the failure stack. Must be a four-byte value. Assumes the variable `fail_stack'. Probably should only be called from within `PUSH_FAILURE_POINT'. */ #define PUSH_FAILURE_ITEM(item) \ fail_stack.stack[fail_stack.avail++] = (fail_stack_elt_t) item /* The complement operation. Assumes `fail_stack' is nonempty. */ #define POP_FAILURE_ITEM() fail_stack.stack[--fail_stack.avail] /* Used to omit pushing failure point id's when we're not debugging. */ #ifdef DEBUG #define DEBUG_PUSH PUSH_FAILURE_ITEM #define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_ITEM () #else #define DEBUG_PUSH(item) #define DEBUG_POP(item_addr) #endif /* Push the information about the state we will need if we ever fail back to it. Requires variables fail_stack, regstart, regend, reg_info, and num_regs be declared. DOUBLE_FAIL_STACK requires `destination' be declared. Does `return FAILURE_CODE' if runs out of memory. */ #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \ do { \ char *destination; \ /* Must be int, so when we don't save any registers, the arithmetic \ of 0 + -1 isn't done as unsigned. */ \ int this_reg; \ \ DEBUG_STATEMENT (failure_id++); \ DEBUG_STATEMENT (nfailure_points_pushed++); \ DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \ DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\ DEBUG_PRINT2 ("