Notes on portability, and on when #include <linux/blah> is appropriate.
[oweals/busybox.git] / findutils / grep.c
index 323e4afc68fa66d71518ccfc179ade1651abcebb..e5b5e3242dfd6b23419c67926ac3f8d989e299ac 100644 (file)
@@ -11,8 +11,9 @@
 /* BB_AUDIT GNU defects - always acts as -a.  */
 /* http://www.opengroup.org/onlinepubs/007904975/utilities/grep.html */
 /*
- * Apr 2004 by Vladimir Oleynik <dzo@simtreas.ru> -
+ * 2004,2006 (C) Vladimir Oleynik <dzo@simtreas.ru> -
  * correction "-e pattern1 -e pattern2" logic and more optimizations.
+ * precompiled regex
 */
 
 #include <stdio.h>
@@ -82,6 +83,13 @@ static int last_line_printed;
 static llist_t *pattern_head;   /* growable list of patterns to match */
 static char *cur_file;          /* the current file we are reading */
 
+typedef struct GREP_LIST_DATA {
+       char *pattern;
+       regex_t preg;
+#define PATTERN_MEM_A 1
+#define COMPILED 2
+       int flg_mem_alocated_compiled;
+} grep_list_data_t;
 
 static void print_line(const char *line, int linenum, char decoration)
 {
@@ -115,12 +123,14 @@ static int grep_file(FILE *file)
 
        while ((line = bb_get_chomped_line_from_file(file)) != NULL) {
                llist_t *pattern_ptr = pattern_head;
+               grep_list_data_t * gl;
 
                linenum++;
                ret = 0;
                while (pattern_ptr) {
+                       gl = (grep_list_data_t *)pattern_ptr->data;
                        if (FGREP_FLAG) {
-                               ret = strstr(line, pattern_ptr->data) != NULL;
+                               ret = strstr(line, gl->pattern) != NULL;
                        } else {
                                /*
                                 * test for a postitive-assertion match (regexec returns success (0)
@@ -128,10 +138,11 @@ static int grep_file(FILE *file)
                                 * match (regexec returns failure (REG_NOMATCH) and the user specified
                                 * invert search)
                                 */
-                               regex_t regex;
-                               xregcomp(&regex, pattern_ptr->data, reflags);
-                               ret |= regexec(&regex, line, 0, NULL, 0) == 0;
-                               regfree(&regex);
+                               if(!(gl->flg_mem_alocated_compiled & COMPILED)) {
+                                       gl->flg_mem_alocated_compiled |= COMPILED;
+                                       xregcomp(&(gl->preg), gl->pattern, reflags);
+                               }
+                               ret |= regexec(&(gl->preg), line, 0, NULL, 0) == 0;
                        }
                        pattern_ptr = pattern_ptr->link;
                } /* while (pattern_ptr) */
@@ -230,6 +241,25 @@ static int grep_file(FILE *file)
        return nmatches;
 }
 
+#if ENABLE_FEATURE_CLEAN_UP
+#define new_grep_list_data(p, m) add_grep_list_data(p, m)
+static char * add_grep_list_data(char *pattern, int flg_used_mem)
+#else
+#define new_grep_list_data(p, m) add_grep_list_data(p)
+static char * add_grep_list_data(char *pattern)
+#endif
+{
+       grep_list_data_t *gl = xmalloc(sizeof(grep_list_data_t));
+       gl->pattern = pattern;
+#if ENABLE_FEATURE_CLEAN_UP
+       gl->flg_mem_alocated_compiled = flg_used_mem;
+#else
+       gl->flg_mem_alocated_compiled = 0;
+#endif
+       return (char *)gl;
+}
+
+
 static void load_regexes_from_file(llist_t *fopt)
 {
        char *line;
@@ -243,13 +273,14 @@ static void load_regexes_from_file(llist_t *fopt)
                free(cur);
                f = bb_xfopen(ffile, "r");
                while ((line = bb_get_chomped_line_from_file(f)) != NULL) {
-                       pattern_head = llist_add_to(pattern_head, line);
+                       pattern_head = llist_add_to(pattern_head,
+                               new_grep_list_data(line, PATTERN_MEM_A));
                }
        }
 }
 
 
-extern int grep_main(int argc, char **argv)
+int grep_main(int argc, char **argv)
 {
        FILE *file;
        int matched;
@@ -264,7 +295,7 @@ extern int grep_main(int argc, char **argv)
        char *slines_before;
        char *Copt;
 
-       bb_opt_complementally = "H-h:e*:f*:C-AB";
+       bb_opt_complementally = "H-h:e::f::C-AB";
        opt = bb_getopt_ulflags(argc, argv,
                GREP_OPTS GREP_OPT_CONTEXT OPT_EGREP,
                &pattern_head, &fopt,
@@ -296,10 +327,10 @@ extern int grep_main(int argc, char **argv)
                lines_after = 0;
        } else if(lines_before > 0)
                before_buf = (char **)xcalloc(lines_before, sizeof(char *));
-       }
+  }
 #else
        /* with auto sanity checks */
-       bb_opt_complementally = "H-h:e*:f*:c-n:q-n:l-n";
+       bb_opt_complementally = "H-h:e::f::c-n:q-n:l-n";
        opt = bb_getopt_ulflags(argc, argv, GREP_OPTS OPT_EGREP,
                &pattern_head, &fopt);
 #endif
@@ -309,6 +340,13 @@ extern int grep_main(int argc, char **argv)
                print_filename++;
        if(opt & GREP_OPT_h)
                print_filename--;
+       if (pattern_head != NULL) {
+               /* convert char *argv[] to grep_list_data_t */
+               llist_t *cur;
+
+               for(cur = pattern_head; cur; cur = cur->link)
+                       cur->data = new_grep_list_data(cur->data, 0);
+       }
        if(opt & GREP_OPT_f)
                load_regexes_from_file(fopt);
 
@@ -333,7 +371,9 @@ extern int grep_main(int argc, char **argv)
                if (*argv == NULL)
                        bb_show_usage();
                else {
-                       pattern_head = llist_add_to(pattern_head, *argv++);
+                       char *pattern = new_grep_list_data(*argv++, 0);
+
+                       pattern_head = llist_add_to(pattern_head, pattern);
                        argc--;
                }
        }
@@ -373,14 +413,20 @@ extern int grep_main(int argc, char **argv)
        }
 
        /* destroy all the elments in the pattern list */
-       if (ENABLE_FEATURE_CLEAN_UP)
-       while (pattern_head) {
-               llist_t *pattern_head_ptr = pattern_head;
-
-               pattern_head = pattern_head->link;
-               free(pattern_head_ptr);
+       if (ENABLE_FEATURE_CLEAN_UP) {
+               while (pattern_head) {
+                       llist_t *pattern_head_ptr = pattern_head;
+                       grep_list_data_t *gl =
+                               (grep_list_data_t *)pattern_head_ptr->data;
+
+                       pattern_head = pattern_head->link;
+                       if((gl->flg_mem_alocated_compiled & PATTERN_MEM_A))
+                               free(gl->pattern);
+                       if((gl->flg_mem_alocated_compiled & COMPILED))
+                               regfree(&(gl->preg));
+                       free(pattern_head_ptr);
+               }
        }
-
        /* 0 = success, 1 = failed, 2 = error */
        /* If the -q option is specified, the exit status shall be zero
         * if an input line is selected, even if an error was detected.  */