diff options
| -rw-r--r-- | src/search.c | 81 |
1 files changed, 55 insertions, 26 deletions
diff --git a/src/search.c b/src/search.c index 7f006883270..f3835ff0743 100644 --- a/src/search.c +++ b/src/search.c @@ -592,6 +592,35 @@ search_command (string, bound, noerror, count, direction, RE) return make_number (np); } +static int +trivial_regexp_p (regexp) + Lisp_Object regexp; +{ + int len = XSTRING (regexp)->size; + unsigned char *s = XSTRING (regexp)->data; + unsigned char c; + while (--len >= 0) + { + switch (*s++) + { + case '.': case '*': case '+': case '?': case '[': case '^': case '$': + return 0; + case '\\': + if (--len < 0) + return 0; + switch (*s++) + { + case '|': case '(': case ')': case '`': case '\'': case 'b': + case 'B': case '<': case '>': case 'w': case 'W': case 's': + case 'S': case '1': case '2': case '3': case '4': case '5': + case '6': case '7': case '8': case '9': + return 0; + } + } + } + return 1; +} + /* Search for the n'th occurrence of STRING in the current buffer, starting at position POS and stopping at position LIM, treating PAT as a literal string if RE is false or as @@ -636,32 +665,10 @@ search_buffer (string, pos, lim, n, RE, trt, inverse_trt) if (n == 0) return pos; - if (RE) - compile_pattern (string, &searchbuf, &search_regs, (char *) trt); - - if (RE /* Here we detect whether the */ - /* generality of an RE search is */ - /* really needed. */ - /* first item is "exact match" */ - && *(searchbuf.buffer) == (char) RE_EXACTN_VALUE - && searchbuf.buffer[1] + 2 == searchbuf.used) /*first is ONLY item */ + if (RE && !trivial_regexp_p (string)) { - RE = 0; /* can do straight (non RE) search */ - pat = (base_pat = (unsigned char *) searchbuf.buffer + 2); - /* trt already applied */ - len = searchbuf.used - 2; - } - else if (!RE) - { - pat = (unsigned char *) alloca (len); + compile_pattern (string, &searchbuf, &search_regs, (char *) trt); - for (i = len; i--;) /* Copy the pattern; apply trt */ - *pat++ = (((int) trt) ? trt [*base_pat++] : *base_pat++); - pat -= len; base_pat = pat; - } - - if (RE) - { immediate_quit = 1; /* Quit immediately if user types ^G, because letting this function finish can take too long. */ @@ -693,7 +700,9 @@ search_buffer (string, pos, lim, n, RE, trt, inverse_trt) /* Don't allow match past current point */ pos - BEGV); if (val == -2) - matcher_overflow (); + { + matcher_overflow (); + } if (val >= 0) { j = BEGV; @@ -721,7 +730,9 @@ search_buffer (string, pos, lim, n, RE, trt, inverse_trt) pos - BEGV, lim - pos, &search_regs, lim - BEGV); if (val == -2) - matcher_overflow (); + { + matcher_overflow (); + } if (val >= 0) { j = BEGV; @@ -752,6 +763,24 @@ search_buffer (string, pos, lim, n, RE, trt, inverse_trt) #else BM_tab = (int *) alloca (0400 * sizeof (int)); #endif + { + unsigned char *patbuf = (unsigned char *) alloca (len); + pat = patbuf; + while (--len >= 0) + { + /* If we got here and the RE flag is set, it's because we're + dealing with a regexp known to be trivial, so the backslash + just quotes the next character. */ + if (RE && *base_pat == '\\') + { + len--; + base_pat++; + } + *pat++ = (trt ? trt[*base_pat++] : *base_pat++); + } + len = pat - patbuf; + pat = base_pat = patbuf; + } /* The general approach is that we are going to maintain that we know */ /* the first (closest to the present position, in whatever direction */ /* we're searching) character that could possibly be the last */ |