erase_mtab: do not limit ourself to 40 mtab entries

1 files changed, 21 insertions, 32 deletions

diff --git a/libbb/mtab.c b/libbb/mtab.c
index cce1aac5c..18386efb5 100644
--- a/libbb/mtab.c
+++ b/libbb/mtab.c
@@ -7,53 +7,42 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-#include <stdlib.h>
-#include <unistd.h>
-#include <errno.h>
-#include <string.h>
-#include <stdio.h>
 #include <mntent.h>
 #include "libbb.h"
 
-#define MTAB_MAX_ENTRIES 40
-
-#ifdef CONFIG_FEATURE_MTAB_SUPPORT
+#if ENABLE_FEATURE_MTAB_SUPPORT
 void erase_mtab(const char *name)
 {
-	struct mntent entries[MTAB_MAX_ENTRIES];
-	int count = 0;
-	FILE *mountTable = setmntent(bb_path_mtab_file, "r");
+	struct mntent *entries = NULL;
+	int i, count = 0;
+	FILE *mountTable;
 	struct mntent *m;
 
-	/* Check if reading the mtab file failed */
-	if (mountTable == 0
-			/* Bummer.  fall back on trying the /proc filesystem */
-			&& (mountTable = setmntent("/proc/mounts", "r")) == 0) {
+	mountTable = setmntent(bb_path_mtab_file, "r");
+	/* Bummer. Fall back on trying the /proc filesystem */
+	if (!mountTable) mountTable = setmntent("/proc/mounts", "r");
+	if (!mountTable) {
 		bb_perror_msg(bb_path_mtab_file);
 		return;
 	}
 
-	while (((m = getmntent(mountTable)) != 0) && (count < MTAB_MAX_ENTRIES))
-	{
-		entries[count].mnt_fsname = strdup(m->mnt_fsname);
-		entries[count].mnt_dir = strdup(m->mnt_dir);
-		entries[count].mnt_type = strdup(m->mnt_type);
-		entries[count].mnt_opts = strdup(m->mnt_opts);
-		entries[count].mnt_freq = m->mnt_freq;
-		entries[count].mnt_passno = m->mnt_passno;
-		count++;
+	while ((m = getmntent(mountTable)) != 0) {
+		i = count++;
+		entries = xrealloc(entries, count * sizeof(entries[0]));
+		entries[i].mnt_fsname = xstrdup(m->mnt_fsname);
+		entries[i].mnt_dir = xstrdup(m->mnt_dir);
+		entries[i].mnt_type = xstrdup(m->mnt_type);
+		entries[i].mnt_opts = xstrdup(m->mnt_opts);
+		entries[i].mnt_freq = m->mnt_freq;
+		entries[i].mnt_passno = m->mnt_passno;
 	}
 	endmntent(mountTable);
-	if ((mountTable = setmntent(bb_path_mtab_file, "w"))) {
-		int i;
 
+	mountTable = setmntent(bb_path_mtab_file, "w");
+	if (mountTable) {
 		for (i = 0; i < count; i++) {
-			int result = (strcmp(entries[i].mnt_fsname, name) == 0
-						  || strcmp(entries[i].mnt_dir, name) == 0);
-
-			if (result)
-				continue;
-			else
+			if (strcmp(entries[i].mnt_fsname, name) != 0
+			 && strcmp(entries[i].mnt_dir, name) != 0)
 				addmntent(mountTable, &entries[i]);
 		}
 		endmntent(mountTable);