last_patch95 from vodz:
[oweals/busybox.git] / findutils / grep.c
index 3779e5510a9eda7ea7ae988f140bfc40b003e63c..241099c79808c9f020614f3bf1675c8c66f6bbcd 100644 (file)
 /*
- * Copyright (c) 1999 by David I. Bell
- * Permission is granted to use, distribute, or modify this source,
- * provided that this copyright notice remains intact.
+ * Mini grep implementation for busybox using libc regex.
  *
- * The "grep" command, taken from sash.
- * This provides basic file searching.
+ * Copyright (C) 1999,2000,2001 by Lineo, inc. and Mark Whitley
+ * Copyright (C) 1999,2000,2001 by Mark Whitley <markw@codepoet.org> 
+ *
+ * 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 of the License, 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  *
- * Permission to distribute this code under the GPL has been granted.
- * Modified for busybox by Erik Andersen <andersee@debian.org> <andersen@lineo.com>
  */
-
-#include "internal.h"
-#ifdef BB_GREP
+/*
+ * Jun 2003 by Vladimir Oleynik <dzo@simtreas.ru> -
+ * correction "-e pattern1 -e -e pattern2" logic and more optimizations.
+*/
 
 #include <stdio.h>
-#include <dirent.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <regex.h>
+#include <string.h>
 #include <errno.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <time.h>
-#include <ctype.h>
-
-
-const char grep_usage[] =
-"Search the input file(s) for lines matching the given pattern.\n"
-"\tI search stdin if no files are given.\n"
-"\tI can't grok full regular expressions.\n"
-"usage: grep [in] PATTERN [FILES]...\n"
-"\ti=ignore case, n=list line numbers\n";
+#include "busybox.h"
+
+
+/* options */
+#define GREP_OPTS "lnqvscFiHhe:f:"
+#define GREP_OPT_l 1
+static char print_files_with_matches;
+#define GREP_OPT_n 2
+static char print_line_num;
+#define GREP_OPT_q 4
+static char be_quiet;
+#define GREP_OPT_v 8
+typedef char invert_search_t;
+static invert_search_t invert_search;
+#define GREP_OPT_s 16
+static char suppress_err_msgs;
+#define GREP_OPT_c 32
+static char print_match_counts;
+#define GREP_OPT_F 64
+static char fgrep_flag;
+#define GREP_OPT_i 128
+#define GREP_OPT_H 256
+#define GREP_OPT_h 512
+#define GREP_OPT_e 1024
+#define GREP_OPT_f 2048
+#ifdef CONFIG_FEATURE_GREP_CONTEXT
+#define GREP_OPT_CONTEXT "A:B:C"
+#define GREP_OPT_A 4096
+#define GREP_OPT_B 8192
+#define GREP_OPT_C 16384
+#define GREP_OPT_E 32768U
+#else
+#define GREP_OPT_CONTEXT ""
+#define GREP_OPT_E 4096
+#endif
+#ifdef CONFIG_FEATURE_GREP_EGREP_ALIAS
+# define OPT_EGREP "E"
+#else
+# define OPT_EGREP ""
+#endif
 
+static int reflags;
+static int print_filename;
 
+#ifdef CONFIG_FEATURE_GREP_CONTEXT
+static int lines_before;
+static int lines_after;
+static char **before_buf;
+static int last_line_printed;
+#endif /* CONFIG_FEATURE_GREP_CONTEXT */
 
-static BOOL    search
-       (const char * string, const char * word, BOOL ignoreCase);
+/* globals used internally */
+static llist_t *pattern_head;   /* growable list of patterns to match */
+static char *cur_file;          /* the current file we are reading */
 
 
-extern int 
-grep_main(struct FileInfo * unused, int argc, char ** argv)
+static void print_line(const char *line, int linenum, char decoration)
 {
-       FILE *          fp;
-       const char *    word;
-       const char *    name;
-       const char *    cp;
-       BOOL            tellName;
-       BOOL            ignoreCase;
-       BOOL            tellLine;
-       long            line;
-       char            buf[BUF_SIZE];
-
-       ignoreCase = FALSE;
-       tellLine = FALSE;
-
-       argc--;
-       argv++;
-       if (argc < 1)
-       {
-               fprintf(stderr, "%s", grep_usage);
-               return 1;
+#ifdef CONFIG_FEATURE_GREP_CONTEXT
+       /* possibly print the little '--' seperator */
+       if ((lines_before || lines_after) && last_line_printed &&
+                       last_line_printed < linenum - 1) {
+               puts("--");
        }
+       last_line_printed = linenum;
+#endif
+       if (print_filename)
+               printf("%s%c", cur_file, decoration);
+       if (print_line_num)
+               printf("%i%c", linenum, decoration);
+       puts(line);
+}
 
-       if (**argv == '-')
-       {
-               argc--;
-               cp = *argv++;
+extern void xregcomp(regex_t *preg, const char *regex, int cflags);
 
-               while (*++cp) switch (*cp)
-               {
-                       case 'i':
-                               ignoreCase = TRUE;
-                               break;
 
-                       case 'n':
-                               tellLine = TRUE;
+static int grep_file(FILE *file)
+{
+       char *line;
+       invert_search_t ret;
+       int linenum = 0;
+       int nmatches = 0;
+#ifdef CONFIG_FEATURE_GREP_CONTEXT
+       int print_n_lines_after = 0;
+       int curpos = 0; /* track where we are in the circular 'before' buffer */
+       int idx = 0; /* used for iteration through the circular buffer */
+#endif /* CONFIG_FEATURE_GREP_CONTEXT */ 
+
+       while ((line = bb_get_chomped_line_from_file(file)) != NULL) {
+               llist_t *pattern_ptr = pattern_head;
+
+               linenum++;
+               ret = 0;
+               while (pattern_ptr) {
+                       if (fgrep_flag) {
+                               ret = strstr(line, pattern_ptr->data) != NULL;
+                       } else {
+                               /*
+                                * test for a postitive-assertion match (regexec returns success (0)
+                                * and the user did not specify invert search), or a negative-assertion
+                                * 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 (!ret)
                                break;
+                       pattern_ptr = pattern_ptr->link;
+               } /* while (pattern_ptr) */
+
+               if ((ret ^ invert_search)) {
+
+                       if (print_files_with_matches || be_quiet)
+                               free(line);
+
+                       /* if we found a match but were told to be quiet, stop here */
+                               if (be_quiet)
+                               return -1;
+
+                               /* keep track of matches */
+                               nmatches++;
+
+                               /* if we're just printing filenames, we stop after the first match */
+                               if (print_files_with_matches)
+                                       break;
+
+                               /* print the matched line */
+                               if (print_match_counts == 0) {
+#ifdef CONFIG_FEATURE_GREP_CONTEXT
+                                       int prevpos = (curpos == 0) ? lines_before - 1 : curpos - 1;
+
+                                       /* if we were told to print 'before' lines and there is at least
+                                        * one line in the circular buffer, print them */
+                                       if (lines_before && before_buf[prevpos] != NULL) {
+                                               int first_buf_entry_line_num = linenum - lines_before;
+
+                                               /* advance to the first entry in the circular buffer, and
+                                                * figure out the line number is of the first line in the
+                                                * buffer */
+                                               idx = curpos;
+                                               while (before_buf[idx] == NULL) {
+                                                       idx = (idx + 1) % lines_before;
+                                                       first_buf_entry_line_num++;
+                                               }
+
+                                               /* now print each line in the buffer, clearing them as we go */
+                                               while (before_buf[idx] != NULL) {
+                                                       print_line(before_buf[idx], first_buf_entry_line_num, '-');
+                                                       free(before_buf[idx]);
+                                                       before_buf[idx] = NULL;
+                                                       idx = (idx + 1) % lines_before;
+                                                       first_buf_entry_line_num++;
+                                               }
+                                       }
+
+                                       /* make a note that we need to print 'after' lines */
+                                       print_n_lines_after = lines_after;
+#endif /* CONFIG_FEATURE_GREP_CONTEXT */ 
+                                       print_line(line, linenum, ':');
+                               }
+                       }
+#ifdef CONFIG_FEATURE_GREP_CONTEXT
+                       else { /* no match */
+                               /* Add the line to the circular 'before' buffer */
+                               if(lines_before) {
+                                       free(before_buf[curpos]);
+                                       before_buf[curpos] = bb_xstrdup(line);
+                                       curpos = (curpos + 1) % lines_before;
+                               }
+                       }
 
-                       default:
-                               fprintf(stderr, "Unknown option\n");
-                               return 1;
-               }
+                       /* if we need to print some context lines after the last match, do so */
+                       if (print_n_lines_after && (last_line_printed != linenum)) {
+                               print_line(line, linenum, '-');
+                               print_n_lines_after--;
+                       }
+#endif /* CONFIG_FEATURE_GREP_CONTEXT */ 
+               free(line);
        }
 
-       word = *argv++;
-       argc--;
-
-       tellName = (argc > 1);
-
-       while (argc-- > 0)
-       {
-               name = *argv++;
-
-               fp = fopen(name, "r");
-
-               if (fp == NULL)
-               {
-                       perror(name);
-
-                       continue;
-               }
-
-               line = 0;
-
-               while (fgets(buf, sizeof(buf), fp))
-               {
-                       line++;
-
-                       cp = &buf[strlen(buf) - 1];
-
-                       if (*cp != '\n')
-                               fprintf(stderr, "%s: Line too long\n", name);
 
-                       if (search(buf, word, ignoreCase))
-                       {
-                               if (tellName)
-                                       printf("%s: ", name);
+       /* special-case file post-processing for options where we don't print line
+        * matches, just filenames and possibly match counts */
 
-                               if (tellLine)
-                                       printf("%ld: ", line);
+       /* grep -c: print [filename:]count, even if count is zero */
+       if (print_match_counts) {
+               if (print_filename)
+                       printf("%s:", cur_file);
+                   printf("%d\n", nmatches);
+       }
 
-                               fputs(buf, stdout);
-                       }
-               }
+       /* grep -l: print just the filename, but only if we grepped the line in the file  */
+       if (print_files_with_matches && nmatches > 0) {
+               puts(cur_file);
+       }
 
-               if (ferror(fp))
-                       perror(name);
+       return nmatches;
+}
 
-               fclose(fp);
+static void load_regexes_from_file(llist_t *fopt)
+{
+       char *line;
+       FILE *f;
+
+       while(fopt) {
+               llist_t *cur = fopt;
+               char *ffile = cur->data;
+
+               fopt = cur->link;
+               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);
+       }
        }
-       return 0;
 }
 
 
-/*
- * See if the specified word is found in the specified string.
- */
-static BOOL
-search(const char * string, const char * word, BOOL ignoreCase)
+extern int grep_main(int argc, char **argv)
 {
-       const char *    cp1;
-       const char *    cp2;
-       int             len;
-       int             lowFirst;
-       int             ch1;
-       int             ch2;
-
-       len = strlen(word);
-
-       if (!ignoreCase)
-       {
-               while (TRUE)
-               {
-                       string = strchr(string, word[0]);
-
-                       if (string == NULL)
-                               return FALSE;
-
-                       if (memcmp(string, word, len) == 0)
-                               return TRUE;
-
-                       string++;
+       FILE *file;
+       int matched;
+       unsigned long opt;
+       llist_t *fopt;
+
+       /* do normal option parsing */
+#ifdef CONFIG_FEATURE_GREP_CONTEXT
+  {
+       char *junk;
+       char *slines_after;
+       char *slines_before;
+       char *Copt;
+
+       bb_opt_complementaly = "H-h:e*:f*:C-AB";
+       opt = bb_getopt_ulflags(argc, argv,
+               GREP_OPTS GREP_OPT_CONTEXT OPT_EGREP,
+               &pattern_head, &fopt,
+               &slines_after, &slines_before, &Copt);
+
+       if(opt & GREP_OPT_C) {
+               /* C option unseted A and B options, but next -A or -B
+                  may be ovewrite own option */
+               if(!(opt & GREP_OPT_A))         /* not overwtited */
+                       slines_after = Copt;
+               if(!(opt & GREP_OPT_B))         /* not overwtited */
+                       slines_before = Copt;
+               opt |= GREP_OPT_A|GREP_OPT_B;   /* set for parse now */
+       }
+       if(opt & GREP_OPT_A) {
+               lines_after = strtoul(slines_after, &junk, 10);
+                               if(*junk != '\0')
+                                       bb_error_msg_and_die("invalid context length argument");
+       }
+       if(opt & GREP_OPT_B) {
+               lines_before = strtoul(slines_before, &junk, 10);
+                               if(*junk != '\0')
+                                       bb_error_msg_and_die("invalid context length argument");
                }
+       /* sanity checks after parse may be invalid numbers ;-) */
+       if ((opt & (GREP_OPT_c|GREP_OPT_q|GREP_OPT_l))) {
+               opt &= ~GREP_OPT_n;
+               lines_before = 0;
+               lines_after = 0;
+       } else if(lines_before > 0)
+               before_buf = (char **)xcalloc(lines_before, sizeof(char *));
        }
+#else
+       /* with auto sanity checks */
+       bb_opt_complementaly = "H-h:e*:f*:c-n:q-n:l-n";
+       opt = bb_getopt_ulflags(argc, argv, GREP_OPTS OPT_EGREP,
+               &pattern_head, &fopt);
 
-       /*
-        * Here if we need to check case independence.
-        * Do the search by lower casing both strings.
-        */
-       lowFirst = *word;
-
-       if (isupper(lowFirst))
-               lowFirst = tolower(lowFirst);
-
-       while (TRUE)
-       {
-               while (*string && (*string != lowFirst) &&
-                       (!isupper(*string) || (tolower(*string) != lowFirst)))
-               {
-                       string++;
+#endif
+       print_files_with_matches = opt & GREP_OPT_l;
+       print_line_num = opt & GREP_OPT_n;
+       be_quiet = opt & GREP_OPT_q;
+       invert_search = (opt & GREP_OPT_v) != 0;        /* 0 | 1 */
+       suppress_err_msgs = opt & GREP_OPT_s;
+       print_match_counts = opt & GREP_OPT_c;
+       fgrep_flag = opt & GREP_OPT_F;
+       if(opt & GREP_OPT_H)
+               print_filename++;
+       if(opt & GREP_OPT_h)
+               print_filename--;
+       if(opt & GREP_OPT_f)
+               load_regexes_from_file(fopt);
+
+#ifdef CONFIG_FEATURE_GREP_EGREP_ALIAS
+       if(bb_applet_name[0] == 'e' || (opt & GREP_OPT_E))
+               reflags = REG_EXTENDED | REG_NOSUB;
+       else
+#endif
+               reflags = REG_NOSUB;
+
+       if(opt & GREP_OPT_i)
+               reflags |= REG_ICASE;
+
+       argv += optind;
+       argc -= optind;
+
+       /* if we didn't get a pattern from a -e and no command file was specified,
+        * argv[optind] should be the pattern. no pattern, no worky */
+       if (pattern_head == NULL) {
+               if (*argv == NULL)
+                       bb_show_usage();
+               else {
+                       pattern_head = llist_add_to(pattern_head, *argv++);
+                       argc--;
                }
+       }
 
-               if (*string == '\0')
-                       return FALSE;
-
-               cp1 = string;
-               cp2 = word;
-
-               do
-               {
-                       if (*cp2 == '\0')
-                               return TRUE;
-
-                       ch1 = *cp1++;
-
-                       if (isupper(ch1))
-                               ch1 = tolower(ch1);
-
-                       ch2 = *cp2++;
-
-                       if (isupper(ch2))
-                               ch2 = tolower(ch2);
+       /* argv[(optind)..(argc-1)] should be names of file to grep through. If
+        * there is more than one file to grep, we will print the filenames */
+       if (argc > 1) {
+               print_filename++;
 
+       /* If no files were specified, or '-' was specified, take input from
+        * stdin. Otherwise, we grep through all the files specified. */
+       } else if (argc == 0) {
+               argc++;
+       }
+       matched = 0;
+       while (argc--) {
+               cur_file = *argv++;
+               if(!cur_file || (*cur_file == '-' && !cur_file[1])) {
+                       cur_file = "-";
+                       file = stdin;
+               } else {
+                       file = fopen(cur_file, "r");
+               }
+                       if (file == NULL) {
+                               if (!suppress_err_msgs)
+                                       bb_perror_msg("%s", cur_file);
+               } else {
+                       matched += grep_file(file);
+                       if(matched < 0) {
+                               /* we found a match but were told to be quiet, stop here and
+                               * return success */
+                               break;
+                       }
+                               fclose(file);
+                       }
                }
-               while (ch1 == ch2);
 
-               string++;
-       }
-}
+#ifdef CONFIG_FEATURE_CLEAN_UP
+       /* destroy all the elments in the pattern list */
+       while (pattern_head) {
+               llist_t *pattern_head_ptr = pattern_head;
 
+               pattern_head = pattern_head->link;
+               free(pattern_head_ptr);
+       }
 #endif
-/* END CODE */
+
+       return !matched; /* invert return value 0 = success, 1 = failed */
+}