X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=umount.c;h=3e23b9705edf3e660f277fca16eadf945d496ded;hb=4949faf4b2090ca23c2aeb34535fdbe57754913a;hp=b65caf76e21eb049c9e59c463bbabc4320ca1c1a;hpb=fac10d7c59f7db0facd5fb94de273310b9ec86e6;p=oweals%2Fbusybox.git

diff --git a/umount.c b/umount.c
index b65caf76e..3e23b9705 100644
--- a/umount.c
+++ b/umount.c
@@ -1,8 +1,9 @@
+/* vi: set sw=4 ts=4: */
 /*
  * Mini umount implementation for busybox
  *
  *
- * Copyright (C) 1999 by Lineo, inc.
+ * Copyright (C) 1999,2000,2001 by Lineo, inc.
  * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
  *
  * This program is free software; you can redistribute it and/or modify
@@ -21,230 +22,268 @@
  *
  */
 
-#include "internal.h"
 #include <stdio.h>
-#include <sys/mount.h>
 #include <mntent.h>
-#include <fstab.h>
 #include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include "busybox.h"
 
-static const char umount_usage[] = 
-"umount [flags] filesystem|directory\n\n"
-"Flags:\n"
-"\t-a:\tUnmount all file systems"
-#ifdef BB_MTAB
-" in /etc/mtab\n\t-n:\tDon't erase /etc/mtab entries\n"
-#else
-"\n"
-#endif
-#ifdef BB_FEATURE_REMOUNT
-"\t-r:\tTry to remount devices as read-only if mount is busy\n"
-#endif
-;
+
+static const int MNT_FORCE = 1;
+static const int MS_MGC_VAL = 0xc0ed0000; /* Magic number indicatng "new" flags */
+static const int MS_REMOUNT = 32;	/* Alter flags of a mounted FS.  */
+static const int MS_RDONLY = 1;	/* Mount read-only.  */
+
+extern int mount (__const char *__special_file, __const char *__dir,
+			__const char *__fstype, unsigned long int __rwflag,
+			__const void *__data);
+extern int umount (__const char *__special_file);
+extern int umount2 (__const char *__special_file, int __flags);
 
 struct _mtab_entry_t {
-  char *device;
-  char *mountpt;
-  struct _mtab_entry_t *next;
+	char *device;
+	char *mountpt;
+	struct _mtab_entry_t *next;
 };
 
 static struct _mtab_entry_t *mtab_cache = NULL;
 
 
 
+#if defined BB_FEATURE_MOUNT_FORCE
+static int doForce = FALSE;
+#endif
+#if defined BB_FEATURE_MOUNT_LOOP
+static int freeLoop = TRUE;
+#endif
+#if defined BB_FEATURE_MTAB_SUPPORT
 static int useMtab = TRUE;
+#endif
 static int umountAll = FALSE;
 static int doRemount = FALSE;
-extern const char mtab_file[]; /* Defined in utility.c */
+extern const char mtab_file[];	/* Defined in utility.c */
 
-#define MIN(x,y) (x > y ? x : y)
 
-static int 
-do_umount(const char* name, int useMtab)
-{
-    int status;
-    char *blockDevice = mtab_getinfo(name, MTAB_GETDEVICE);
 
-    if (blockDevice && strcmp(blockDevice, name) == 0)
-        name = mtab_getinfo(blockDevice, MTAB_GETMOUNTPT);
+/* These functions are here because the getmntent functions do not appear
+ * to be re-entrant, which leads to all sorts of problems when we try to
+ * use them recursively - randolph
+ *
+ * TODO: Perhaps switch to using Glibc's getmntent_r
+ *        -Erik
+ */
+void mtab_read(void)
+{
+	struct _mtab_entry_t *entry = NULL;
+	struct mntent *e;
+	FILE *fp;
 
-    status = umount(name);
+	if (mtab_cache != NULL)
+		return;
 
-#if defined BB_FEATURE_MOUNT_LOOP
-    if (blockDevice != NULL && !strncmp("/dev/loop", blockDevice, 9))
-	/* this was a loop device, delete it */
-	del_loop(blockDevice);
-#endif
-#if defined BB_FEATURE_REMOUNT
-    if ( status != 0 && doRemount == TRUE && errno == EBUSY ) {
-        status = mount(blockDevice, name, NULL, 
-                       MS_MGC_VAL | MS_REMOUNT | MS_RDONLY, NULL);
-	if (status == 0) {
-	    fprintf(stderr, "umount: %s busy - remounted read-only\n", 
-                    blockDevice);
-	    /* TODO: update mtab if BB_MTAB is defined */
-	} else {
-	    fprintf(stderr, "umount: Cannot remount %s read-only\n",
-                    blockDevice);
+	if ((fp = setmntent(mtab_file, "r")) == NULL) {
+		error_msg("Cannot open %s", mtab_file);
+		return;
 	}
-    }
-#endif
-    if ( status == 0 ) {
-#if defined BB_MTAB
-	if ( useMtab==TRUE )
-	    erase_mtab(name);
-#endif
-	return( TRUE);
-    }
-    return(FALSE);
+	while ((e = getmntent(fp))) {
+		entry = xmalloc(sizeof(struct _mtab_entry_t));
+		entry->device = strdup(e->mnt_fsname);
+		entry->mountpt = strdup(e->mnt_dir);
+		entry->next = mtab_cache;
+		mtab_cache = entry;
+	}
+	endmntent(fp);
 }
 
-static int
-umount_all(int useMtab)
+char *mtab_getinfo(const char *match, const char which)
 {
-	int status = TRUE;
-	char *mountpt;
-	void *iter;
+	struct _mtab_entry_t *cur = mtab_cache;
 
-	for (mountpt = mtab_first(&iter); mountpt; mountpt = mtab_next(&iter)) {
-            status=do_umount (mountpt, useMtab);
-            if (status != 0) {
-                /* Don't bother retrying the umount on busy devices */
-		if (errno == EBUSY) {
-                   perror(mountpt);
-		   continue;
-		}
-		status = do_umount (mountpt, useMtab);
-		if (status != 0) {
-                    printf ("Couldn't umount %s on %s: %s\n", 
-                        mountpt, mtab_getinfo(mountpt, MTAB_GETDEVICE), strerror(errno));
+	while (cur) {
+		if (strcmp(cur->mountpt, match) == 0 ||
+			strcmp(cur->device, match) == 0) {
+			if (which == MTAB_GETMOUNTPT) {
+				return cur->mountpt;
+			} else {
+#if !defined BB_FEATURE_MTAB_SUPPORT
+				if (strcmp(cur->device, "/dev/root") == 0) {
+					/* Adjusts device to be the real root device,
+					 * or leaves device alone if it can't find it */
+					find_real_root_device_name( cur->device);
+					return ( cur->device);
+				}
+#endif
+				return cur->device;
+			}
 		}
-            }
-        }
-        return (status);
+		cur = cur->next;
+	}
+	return NULL;
 }
 
-extern int
-umount_main(int argc, char** argv)
+char *mtab_first(void **iter)
 {
-    if (argc < 2) {
-	usage( umount_usage); 
-    }
-
-    /* Parse any options */
-    while (--argc > 0 && **(++argv) == '-') {
-	while (*++(*argv)) switch (**argv) {
-	    case 'a':
-		umountAll = TRUE;
-		break;
-#ifdef BB_MTAB
-	    case 'n':
-		useMtab = FALSE;
-		break;
-#endif
-#ifdef BB_FEATURE_REMOUNT
-	    case 'r':
-		doRemount = TRUE;
-		break;
-#endif
-	    default:
-		usage( umount_usage);
-	}
-    }
-
-    mtab_read();
-    if (umountAll==TRUE) {
-	exit(umount_all(useMtab));
-    }
-    if ( do_umount(*argv,useMtab) == 0 )
-	exit (TRUE);
-    else {
-	perror("umount");
-	exit(FALSE);
-    }
+	struct _mtab_entry_t *mtab_iter;
+
+	if (!iter)
+		return NULL;
+	mtab_iter = mtab_cache;
+	*iter = (void *) mtab_iter;
+	return mtab_next(iter);
 }
 
+char *mtab_next(void **iter)
+{
+	char *mp;
 
+	if (iter == NULL || *iter == NULL)
+		return NULL;
+	mp = ((struct _mtab_entry_t *) (*iter))->mountpt;
+	*iter = (void *) ((struct _mtab_entry_t *) (*iter))->next;
+	return mp;
+}
 
-/* These functions are here because the getmntent functions do not appear
- * to be re-entrant, which leads to all sorts of problems when we try to
- * use them recursively - randolph
- */
-void mtab_read(void)
+/* Don't bother to clean up, since exit() does that 
+ * automagically, so we can save a few bytes */
+#ifdef BB_FEATURE_CLEAN_UP
+void mtab_free(void)
 {
-    struct _mtab_entry_t *entry = NULL;
-    struct mntent *e;
-    FILE *fp;
-  
-    if (mtab_cache != NULL) return;
- 
-    if ((fp = setmntent(mtab_file, "r")) == NULL) {
-        fprintf(stderr, "Cannot open %s\n", mtab_file);
-	return;
-    }
-    while ((e = getmntent(fp))) {
-        entry = malloc(sizeof(struct _mtab_entry_t));
-	entry->device = strdup(e->mnt_fsname);
-	entry->mountpt = strdup(e->mnt_dir);
-	entry->next = mtab_cache;
-	mtab_cache = entry;
-    }
-    endmntent(fp);
+	struct _mtab_entry_t *this, *next;
+
+	this = mtab_cache;
+	while (this) {
+		next = this->next;
+		if (this->device)
+			free(this->device);
+		if (this->mountpt)
+			free(this->mountpt);
+		free(this);
+		this = next;
+	}
 }
+#endif
 
-char *mtab_getinfo(const char *match, const char which)
+static int do_umount(const char *name)
 {
-    struct _mtab_entry_t *cur = mtab_cache;
-    while (cur) {
-        if (strcmp(cur->mountpt, match) == 0 ||
-	    strcmp(cur->device, match) == 0) {
-	    if (which == MTAB_GETMOUNTPT) {
-	        return cur->mountpt;
-	    } else {
-#if !defined BB_MTAB
-                if (strcmp(cur->device, "/dev/root") == 0) {
-                    struct fstab* fstabItem;
-	            fstabItem = getfsfile ("/");
-	            if (fstabItem != NULL) return fstabItem->fs_spec;
-	        }
+	int status;
+	char *blockDevice = mtab_getinfo(name, MTAB_GETDEVICE);
+
+	if (blockDevice && strcmp(blockDevice, name) == 0)
+		name = mtab_getinfo(blockDevice, MTAB_GETMOUNTPT);
+
+	status = umount(name);
+
+#if defined BB_FEATURE_MOUNT_LOOP
+	if (freeLoop == TRUE && blockDevice != NULL && !strncmp("/dev/loop", blockDevice, 9))
+		/* this was a loop device, delete it */
+		del_loop(blockDevice);
+#endif
+#if defined BB_FEATURE_MOUNT_FORCE
+	if (status != 0 && doForce == TRUE) {
+		status = umount2(blockDevice, MNT_FORCE);
+		if (status != 0) {
+			error_msg_and_die("forced umount of %s failed!", blockDevice);
+		}
+	}
 #endif
-	        return cur->device;  
-	    }
+	if (status != 0 && doRemount == TRUE && errno == EBUSY) {
+		status = mount(blockDevice, name, NULL,
+					   MS_MGC_VAL | MS_REMOUNT | MS_RDONLY, NULL);
+		if (status == 0) {
+			error_msg("%s busy - remounted read-only", blockDevice);
+		} else {
+			error_msg("Cannot remount %s read-only", blockDevice);
+		}
 	}
-        cur = cur->next;
-    }
-    return NULL;
+	if (status == 0) {
+#if defined BB_FEATURE_MTAB_SUPPORT
+		if (useMtab == TRUE)
+			erase_mtab(name);
+#endif
+		return (TRUE);
+	}
+	return (FALSE);
 }
 
-char *mtab_first(void **iter)
+static int umount_all(void)
 {
-    struct _mtab_entry_t *mtab_iter;
-    if (!iter) return NULL;
-    mtab_iter = mtab_cache;
-    *iter = (void *)mtab_iter;
-    return mtab_next(iter);
-}
+	int status = TRUE;
+	char *mountpt;
+	void *iter;
 
-char *mtab_next(void **iter)
-{
-    char *mp;
-    if (iter == NULL || *iter == NULL) return NULL;
-    mp = ((struct _mtab_entry_t *)(*iter))->mountpt;
-    *iter = (void *)((struct _mtab_entry_t *)(*iter))->next;
-    return mp;
+	for (mountpt = mtab_first(&iter); mountpt; mountpt = mtab_next(&iter)) {
+		/* Never umount /proc on a umount -a */
+		if (strstr(mountpt, "proc")!= NULL)
+			continue;
+		if (!do_umount(mountpt)) {
+			/* Don't bother retrying the umount on busy devices */
+			if (errno == EBUSY) {
+				perror_msg("%s", mountpt);
+				status = FALSE;
+				continue;
+			}
+			if (!do_umount(mountpt)) {
+				printf("Couldn't umount %s on %s: %s\n",
+					   mountpt, mtab_getinfo(mountpt, MTAB_GETDEVICE),
+					   strerror(errno));
+				status = FALSE;
+			}
+		}
+	}
+	return (status);
 }
 
-void mtab_free(void)
+extern int umount_main(int argc, char **argv)
 {
-    struct _mtab_entry_t *this, *next;
-
-    this = mtab_cache;
-    while (this) {
-      next = this->next;
-      if (this->device) free(this->device);
-      if (this->mountpt) free(this->mountpt);
-      free(this);
-      this = next;
-    }
+	if (argc < 2) {
+		show_usage();
+	}
+#ifdef BB_FEATURE_CLEAN_UP
+	atexit(mtab_free);
+#endif
+
+	/* Parse any options */
+	while (--argc > 0 && **(++argv) == '-') {
+		while (*++(*argv))
+			switch (**argv) {
+			case 'a':
+				umountAll = TRUE;
+				break;
+#if defined BB_FEATURE_MOUNT_LOOP
+			case 'l':
+				freeLoop = FALSE;
+				break;
+#endif
+#ifdef BB_FEATURE_MTAB_SUPPORT
+			case 'n':
+				useMtab = FALSE;
+				break;
+#endif
+#ifdef BB_FEATURE_MOUNT_FORCE
+			case 'f':
+				doForce = TRUE;
+				break;
+#endif
+			case 'r':
+				doRemount = TRUE;
+				break;
+			case 'v':
+				break; /* ignore -v */
+			default:
+				show_usage();
+			}
+	}
+
+	mtab_read();
+	if (umountAll == TRUE) {
+		if (umount_all() == TRUE)
+			return EXIT_SUCCESS;
+		else
+			return EXIT_FAILURE;
+	}
+	if (do_umount(*argv) == TRUE)
+		return EXIT_SUCCESS;
+	perror_msg_and_die("%s", *argv);
 }