stage1: Move the symlink creation from stage1 to init.

In order to run stage1 we now need to do things a little differently,
namely that we move the symlinking fixups into 'init' itself which we will
actually call as a kind of fake switch_root implementation to avoid
hacking dracut too much[1]. As we run stage1 during dracut's 'mount' phase
we should not do the symlink hacks so early otherwise it will mess up
the rest of the dracut initqueue processing.

Currently, the initrd's /usr is nuked and then symlinked, but to
allow for easier debugging I now just bind mount the stage2 /usr over
the top which allows us to unmount it again easily enough if we want to
go back.

We no longer touch the /bin, /sbin or /lib[64] symlinks as these are
relative and simply bind mounting /usr is enough to fix all of them.

1. This scheme will have to change if we eventually swtich to a
systemd based dracut invocation.

7 files changed, 87 insertions, 108 deletions

diff --git a/mdk-stage1/NEWS b/mdk-stage1/NEWS
index 3c65b1bd5..8f2846cbd 100644
--- a/mdk-stage1/NEWS
+++ b/mdk-stage1/NEWS
@@ -1,3 +1,4 @@
+- do initrd symlinking in 'init' rather than 'stage1' (stage1 is now run earlier)
 - build init and stage1 as a shared library (due to bugs in directory handling 
   in dietlibc as exposed in libkmod but also because glibc is already include in
   dracut)
diff --git a/mdk-stage1/init.c b/mdk-stage1/init.c
index 3f912c2ac..6d571a62a 100644
--- a/mdk-stage1/init.c
+++ b/mdk-stage1/init.c
@@ -22,6 +22,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <stdio.h>
+#include <dirent.h>
 #include <string.h>
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -378,7 +379,86 @@ int in_reboot(void)
         return 0;
 }
 
-int exit_value_proceed = 66;
+int recursive_remove(char *file);
+int recursive_remove(char *file)
+{
+	struct stat sb;
+
+	if (lstat(file, &sb) != 0) {
+		printf("failed to stat %s: %d\n", file, errno);
+		return -1;
+	}
+
+	/* only descend into subdirectories if device is same as dir */
+	if (S_ISDIR(sb.st_mode)) {
+		char * strBuf = alloca(strlen(file) + 1024);
+		DIR * dir;
+		struct dirent * d;
+
+		if (!(dir = opendir(file))) {
+			printf("error opening %s: %d\n", file, errno);
+			return -1;
+		}
+		while ((d = readdir(dir))) {
+			if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
+				continue;
+
+			strcpy(strBuf, file);
+			strcat(strBuf, "/");
+			strcat(strBuf, d->d_name);
+
+			if (recursive_remove(strBuf) != 0) {
+				closedir(dir);
+				return -1;
+			}
+		}
+		closedir(dir);
+
+		if (rmdir(file)) {
+			printf("failed to rmdir %s: %d\n", file, errno);
+			return -1;
+		}
+	} else {
+		if (unlink(file) != 0) {
+			printf("failed to remove %s: %d\n", file, errno);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+
+int create_initial_fs_symlinks(char* symlinks)
+{
+        FILE *f;
+        char buf[5000];
+
+        if (!(f = fopen(symlinks, "rb"))) {
+                printf("Error opening symlink definitions file '%s'\n", symlinks);
+                return -1;
+        }
+        while (fgets(buf, sizeof(buf), f)) {
+                char oldpath[500], newpath[500];
+                struct stat sb;
+
+                buf[strlen(buf)-1] = '\0';  // trim \n
+                if (sscanf(buf, "%s %s", oldpath, newpath) != 2) {
+                        sprintf(oldpath, "%s%s", STAGE2_LOCATION, buf);
+                        sprintf(newpath, "%s", buf);
+                }
+                if (lstat(newpath, &sb) == 0)
+                        recursive_remove(newpath);
+                printf("Creating symlink %s -> %s\n", oldpath, newpath);
+                if (symlink(oldpath, newpath)) {
+                        printf("Error creating symlink\n");
+                        return -1;
+                }
+        }
+        fclose(f);
+        return 0;
+}
+
+
 int exit_value_restart = 0x35;
 
 int main(int argc, char **argv)
@@ -454,12 +534,12 @@ int main(int argc, char **argv)
 	if (!testing) 
 		doklog();
 
-	/* Go into normal init mode - keep going, and then do a orderly shutdown
-	   when:
+	if (create_initial_fs_symlinks(STAGE2_LOCATION "/usr/share/symlinks") != 0)
+		fatal_error("Fatal error finishing initialization (could not create symlinks).");
+
+	if (mount(STAGE2_LOCATION "/usr", "/usr", "none", MS_BIND|MS_RDONLY, NULL))
+		fatal_error("Unable to bind mount /usr filesystem from rescue or installer stage2");
 
-	   1) install exits
-	   2) we receive a SIGHUP 
-	*/
 
         do {
 		if (counter == 1) {
diff --git a/mdk-stage1/stage1.c b/mdk-stage1/stage1.c
index ee24bf0a1..4439b7d37 100644
--- a/mdk-stage1/stage1.c
+++ b/mdk-stage1/stage1.c
@@ -344,39 +344,8 @@ static void method_select_and_prepare(void)
 }
 #endif
 
-static enum return_type create_initial_fs_symlinks(char* symlinks)
-{
-        FILE *f;
-        char buf[5000];
-
-        if (scall(!(f = fopen(symlinks, "rb")), "fopen"))
-                return RETURN_ERROR;
-        while (fgets(buf, sizeof(buf), f)) {
-                char oldpath[500], newpath[500];
-                buf[strlen(buf)-1] = '\0';  // trim \n
-                if (sscanf(buf, "%s %s", oldpath, newpath) != 2) {
-                        sprintf(oldpath, "%s%s", STAGE2_LOCATION, buf);
-			sprintf(newpath, "%s", buf);
-                }
-		recursiveRemove_if_it_exists(newpath);
-                log_message("creating symlink %s -> %s", oldpath, newpath);
-                if (scall(symlink(oldpath, newpath), "symlink"))
-                        return RETURN_ERROR;
-        }
-        fclose(f);
-        return RETURN_OK;
-}
-
 void finish_preparing(void)
 {
-	recursiveRemove("/init");
-
-	if (create_initial_fs_symlinks(STAGE2_LOCATION "/usr/share/symlinks") != RETURN_OK)
-		stg1_fatal_message("Fatal error finishing initialization.");
-
-	/* /tmp/syslog is used by the second init, so it must be copied now, not in stage2 */
-	/* we remove it to ensure the old one is not copied over it in stage2 */
-
 #ifdef SPAWN_SHELL
 	if (shell_pid != 0) {
 		int fd;
diff --git a/mdk-stage1/tools.c b/mdk-stage1/tools.c
index aca40c971..78108d6a9 100644
--- a/mdk-stage1/tools.c
+++ b/mdk-stage1/tools.c
@@ -148,65 +148,6 @@ enum return_type copy_file(char * from, char * to, void (*callback_func)(int ove
         }
 }
 
-enum return_type recursiveRemove(char *file) 
-{
-	struct stat sb;
-
-	if (lstat(file, &sb) != 0) {
-		log_message("failed to stat %s: %d", file, errno);
-		return RETURN_ERROR;
-	}
-
-	/* only descend into subdirectories if device is same as dir */
-	if (S_ISDIR(sb.st_mode)) {
-		char * strBuf = alloca(strlen(file) + 1024);
-		DIR * dir;
-		struct dirent * d;
-
-		if (!(dir = opendir(file))) {
-			log_message("error opening %s: %d", file, errno);
-			return RETURN_ERROR;
-		}
-		while ((d = readdir(dir))) {
-			if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
-				continue;
-
-			strcpy(strBuf, file);
-			strcat(strBuf, "/");
-			strcat(strBuf, d->d_name);
-
-			if (recursiveRemove(strBuf) != 0) {
-				closedir(dir);
-				return RETURN_ERROR;
-			}
-		}
-		closedir(dir);
-
-		if (rmdir(file)) {
-			log_message("failed to rmdir %s: %d", file, errno);
-			return RETURN_ERROR;
-		}
-	} else {
-		if (unlink(file) != 0) {
-			log_message("failed to remove %s: %d", file, errno);
-			return RETURN_ERROR;
-		}
-	}
-	return RETURN_OK;
-}
-
-enum return_type recursiveRemove_if_it_exists(char *file) 
-{
-	struct stat sb;
-
-	if (lstat(file, &sb) != 0) {
-		/* if file doesn't exist, simply return OK */
-		return RETURN_OK;
-	}
-
-	return recursiveRemove(file);
-}
-
 enum return_type mount_compressed_image(char *compressed_image,  char *location_mount)
 {
 	if (lomount(compressed_image, location_mount, NULL, 1)) {
diff --git a/mdk-stage1/tools.h b/mdk-stage1/tools.h
index 1b08e42ca..87c0c1d49 100644
--- a/mdk-stage1/tools.h
+++ b/mdk-stage1/tools.h
@@ -29,8 +29,6 @@ int image_has_stage2();
 enum return_type create_IMAGE_LOCATION(char *location_full);
 int ramdisk_possible(void);
 enum return_type copy_file(char * from, char * to, void (*callback_func)(int overall));
-enum return_type recursiveRemove(char *file);
-enum return_type recursiveRemove_if_it_exists(char *file);
 enum return_type preload_mount_compressed_fd(int compressed_fd, int image_size, char *image_name, char *location_mount);
 enum return_type mount_compressed_image(char *compressed_image,  char *location_mount);
 enum return_type mount_compressed_image_may_preload(char *image_name, char *location_mount, int preload);
diff --git a/mdk-stage1/utils.c b/mdk-stage1/utils.c
index af5ee9af3..d861877e4 100644
--- a/mdk-stage1/utils.c
+++ b/mdk-stage1/utils.c
@@ -162,14 +162,6 @@ char * asprintf_(const char *msg, ...)
         return strdup("");
 }
 
-int scall_(int retval, char * msg, char * file, int line)
-{
-	char tmp[5000];
-        sprintf(tmp, "%s(%s:%d) failed", msg, file, line);
-        if (retval)
-                log_perror(tmp);
-        return retval;
-}
 
 void lowercase(char *s)
 {
diff --git a/mdk-stage1/utils.h b/mdk-stage1/utils.h
index d42c52d06..b8a77b0ad 100644
--- a/mdk-stage1/utils.h
+++ b/mdk-stage1/utils.h
@@ -27,9 +27,7 @@ void add_to_env(char * name, char * value);
 char ** list_directory(char * direct);
 int string_array_length(char ** a);
 char * asprintf_(const char *msg, ...);
-int scall_(int retval, char * msg, char * file, int line);
 char *my_dirname(char *path);
-#define scall(retval, msg) scall_(retval, msg, __FILE__, __LINE__)
 void lowercase(char *s);
 
 #define ptr_begins_static_str(pointer,static_str) (!strncmp(pointer,static_str,sizeof(static_str)-1))