archmobile: ldconfig cannot be executed

[harlekin]

When installing the base system using the installer, glibc's scriptlet fails to execute with the following error message:

sh: /media/sd_storage/sbin/ldconfig: file or directory not found

[harlekin]

Condition not present in development version of installer. Will be released soon.

[harlekin]

This issue remains when installing with -b only.

[harlekin]

The information that ldconfig only fails when installing with --build was wrong. This happens because pacman doesn't chroot when trying to execute ldconfig. Thus if qemu-static-arm is not installed in the host system, ldconfig cannot be executed.

Possible work-arounds:

1. Installing qemu-static-arm to the host system should fix the problem.
2. Ignore the error and run ldconfig manually in the chrooted environment (build environment) or on the phone (regular installation)

A proper fix would probably require to patch pacman.

[harlekin]

Here's a patch for pacman (libalpm) fixing the issue in my test cases. Can this be considered a pacman bug and justify opening a ticket?

lib/libalpm/add.c

@@ -887 +887 @@
         }
 
         /* run ldconfig if it exists */
-        _alpm_log(PM_LOG_DEBUG, "running \"ldconfig -r %s\"\n", handle->root);
+        _alpm_log(PM_LOG_DEBUG, "running \"ldconfig\" under chroot (%s)\n",
+                        handle->root);
         _alpm_ldconfig(handle->root);
 
         return(0);

lib/libalpm/remove.c

@@ -395 +395 @@
 
         /* run ldconfig if it exists */
         if(trans->type != PM_TRANS_TYPE_REMOVEUPGRADE) {
-                _alpm_log(PM_LOG_DEBUG, "running \"ldconfig -r %s\"\n", handle->root);
+                _alpm_log(PM_LOG_DEBUG, "running \"ldconfig\" under chroot (%s)\n",
+                        handle->root);
                 _alpm_ldconfig(handle->root);
         }
 

lib/libalpm/util.c

@@ -456 +456 @@
 
 int _alpm_ldconfig(const char *root)
 {
-        char line[PATH_MAX];
-
-        snprintf(line, PATH_MAX, "%setc/ld.so.conf", root);
-        if(access(line, F_OK) == 0) {
-                snprintf(line, PATH_MAX, "%ssbin/ldconfig", root);
-                if(access(line, X_OK) == 0) {
-                        char cmd[PATH_MAX];
-                        snprintf(cmd, PATH_MAX, "%s -r %s", line, root);
-                        system(cmd);
+        pid_t pid;
+        char cwd[PATH_MAX];
+        const char *ldconfig = "/sbin/ldconfig";
+        const char *ldsoconf = "/etc/ld.so.conf";
+        int retval = 0;
+
+        /* Flush open fds before fork() to avoid cloning buffers */
+        fflush(NULL);
+
+        pid = fork();
+        if(pid == -1) {
+                _alpm_log(PM_LOG_ERROR, _("could not fork a new process (%s)\n"),
+                                        strerror(errno));
+                retval = 1;
+        }
+        if(pid == 0) {
+                /* this code runs for the child only (the actual chroot/exec) */
+                _alpm_log(PM_LOG_DEBUG, "chrooting in %s\n", root);
+                if(chroot(root) != 0) {
+                        _alpm_log(PM_LOG_ERROR, _("could not change directory to / (%s)\n"),
+                                        strerror(errno));
+                        exit(1);
+                }
+                if(chdir("/") != 0) {
+                        _alpm_log(PM_LOG_ERROR, _("could not change directory to / (%s)\n"),
+                                        strerror(errno));
+                        exit(1);
+                }
+                /* Somehow it fails if we check for the necessary files using access().
+                 * Any suggestions why? */
+                /*if(access(ldsoconf, F_OK) != 0) {
+                        _alpm_log(PM_LOG_ERROR, _("%s not found\n"),
+                                        ldsoconf, strerror(errno));
+                        exit(1);
+                }
+                if(access(ldconfig, X_OK) != 0) {
+                        _alpm_log(PM_LOG_ERROR, _("%s cannot be executed\n"),
+                                        ldconfig, strerror(errno));
+                        exit(1);
+                }*/
+                if (execl(ldconfig, ldconfig, (char *) NULL) == -1) {
+                        exit(1);
+                }
+        } else {
+                /* this code runs for the parent only (wait on the child) */
+                pid_t retpid;
+                int status;
+                while((retpid = waitpid(pid, &status, 0)) == -1 && errno == EINTR);
+                if(retpid == -1) {
+                        _alpm_log(PM_LOG_ERROR, _("call to waitpid failed (%s)\n"),
+                                        strerror(errno));
+                        retval = 1;
+                } else {
+                        if(WIFEXITED(status)) {
+                                _alpm_log(PM_LOG_DEBUG, "call to waitpid succeeded\n");
+                                if(WEXITSTATUS(status) != 0) {
+                                        retval = 1;
+                                }
+                        }
                 }
         }
+        if(retval != 0) {
+                _alpm_log(PM_LOG_ERROR, _("ldconfig failed to execute correctly\n"));
+        }
 
-        return(0);
+        return(retval);
 }
 
 /* Helper function for comparing strings using the

By the way, does anyone know why checking for access() fails?

[harlekin]

I filed a  bug report for pacman to get some insight from the pacman devs. To my understanding this is a pacman bug. If it is not we'll have to add a work around to the installer.

[harlekin]

PS. The patch attached to pacman's bug report is a modified version of the patch which bypasses the access() misbehaviour and which follows the original pacman code more strictly.

[harlekin]

Apparently a patch by shining has been accepted and will be added to the pacman mainline. I'll fix this ticket once a new pacman snapshot is released and once our pacman packages are recompiled against that version.

[harlekin]

This is fixed in pacman 3.3.0. I am currently uploading the new packages.