Eliminate egrep in Find file feature: 1st Approximation

["Andrew V. Samoilov" <sav bcs zp ua>]

Hi!

This patch eliminates egrep usage in Find file feature. 
So we can search desired regular expression over VFS and in binary files and
on platforms without egrep.

ChangeLog:
	* find.c (get_line_at): New function. Returns malloced null-terminated
	string from file descriptor file_fd. Input is buffered in buf 
	buf_size long. Newline(s) accounted in line variable.

	(search_content): Use get_line_at and regex.

TODO: Move regcomp and regfree calls and r variable from search_content.
Make r static. Inform user about malformed regular experssion (message can be
taken from view.c).
Add get_line_at description in comment.
Remove locate_egrep.

Regards,
Andrew.

Index: find.c
===================================================================
RCS file: /home/sav/.cvsroot/mc/src/find.c,v
retrieving revision 1.37
diff -u -p -r1.37 find.c
--- find.c	27 Apr 2001 10:07:45 -0000	1.37
+++ find.c	28 Aug 2001 06:20:25 -0000
@@ -50,6 +50,12 @@
 #include "cmd.h"		/* view_file_at_line */
 #include "../vfs/vfs.h"
 
+#if defined(HAVE_RX_H) && defined(HAVE_REGCOMP)
+#    include <rx.h>
+#else
+#    include <regex.h>
+#endif
+
 #ifndef PORT_HAS_FLUSH_EVENTS
 #    define x_flush_events()
 #endif
@@ -409,10 +414,52 @@ locate_egrep (void)
 }
 #endif
 
+static char *
+get_line_at (int file_fd, char *buf, int *pos, int *n_read, int buf_size, int *line)
+{
+    char *buffer = 0;
+    int  buffer_size = 0;
+    char ch;
+    int  i = 0;
+
+    for (;;){
+	if (*pos == *n_read){
+	    if ((*n_read = mc_read (file_fd, buf, buf_size)) <= 0)
+		break;
+	    *pos = 0;
+	}
+
+	ch = buf [(*pos)++];
+	/* skip over all the possible zeros in the file */
+	if (ch == 0) {
+	    if (i == 0)
+		continue;
+	    else
+		break;
+	}
+
+	if (i >= buffer_size - 1){
+	    buffer = g_realloc (buffer, buffer_size += 80);
+	}
+
+	buffer [i++] = ch;
+	if (ch == '\n'){
+	    (*line)++;
+	    break;
+	}
+    } 
+
+    if (buffer){
+	buffer [i] = 0;
+    }
+
+    return buffer;
+}
+
 /* 
  * search_content:
  *
- * Search with egrep the global (FIXME) content_pattern string in the
+ * Search the global (FIXME) content_pattern string in the
  * DIRECTORY/FILE.  It will add the found entries to the find listbox.
  */
 static void
@@ -421,12 +468,11 @@ search_content (Dlg_head *h, char *direc
     struct stat s;
     char buffer [BUF_SMALL];
     char *fname, *p;
-    int file_fd, pipe, ignoring;
-    char c;
+    int file_fd;
     int i;
-    pid_t pid;
-    char *egrep_path = "egrep";
-    char *egrep_opts = case_sensitive ? "-n" : "-in";
+    int pos, n_read;
+    regex_t r;
+    int flags = REG_EXTENDED|REG_NOSUB;
 
     fname = concat_dir_and_file (directory, filename);
 
@@ -441,57 +487,33 @@ search_content (Dlg_head *h, char *direc
     if (file_fd == -1)
 	return;
 
-#ifndef GREP_STDIN
-    pipe = mc_doublepopen (file_fd, -1, &pid, egrep_path, egrep_path, egrep_opts, content_pattern, NULL);
-#else /* GREP_STDIN */
-    pipe = mc_doublepopen (file_fd, -1, &pid, egrep_path, egrep_path, egrep_opts, content_pattern, "-", NULL);
-#endif /* GREP STDIN */
-
-    if (pipe == -1){
-	mc_close (file_fd);
-	return;
-    }
-
     g_snprintf (buffer, sizeof (buffer), _("Grepping in %s"), name_trunc (filename, FIND2_X_USE));
 
     status_update (buffer);
     mc_refresh ();
-    p = buffer;
-    ignoring = 0;
 
     enable_interrupt_key ();
     got_interrupt ();
 
-    while ((i = read (pipe, &c, 1)) == 1){
-
-	if (c == '\n'){
-	    p = buffer;
-	    ignoring = 0;
-	}
-
-	if (ignoring)
-	    continue;
-
-	if (c == ':'){
-	    char *the_name;
+    if (!case_sensitive)
+	flags |= REG_ICASE;
 
-	    *p = 0;
-	    ignoring = 1;
-	    the_name = g_strconcat (buffer, ":", filename, NULL);
-	    find_add_match (h, directory, the_name);
-	    g_free (the_name);
-	} else {
-	    if (p - buffer < (sizeof (buffer)-1) && ISASCII (c) && isdigit (c))
-		*p++ = c;
-	    else
-		*p = 0;
+    if (regcomp (&r, content_pattern, flags) == 0){
+	i = 1;
+	pos = 0;
+	n_read = 0;
+
+	while ((p = get_line_at (file_fd, buffer, &pos, &n_read, sizeof (buffer), &i))){
+	    if (regexec (&r, p, 1, 0, 0) == 0){
+		char *the_name = g_strdup_printf ("%d:%s", i, filename);
+		find_add_match (h, directory, the_name);
+		g_free (the_name);
+	    }
+	    g_free (p);
 	}
     }
+    regfree (&r);
     disable_interrupt_key ();
-    if (i == -1)
-	message (1, _(" Find/read "), _(" Problem reading from child "));
-
-    mc_doublepclose (pipe, pid);
     mc_close (file_fd);
 }