discover/boot: Add boot hooks

Add a method of running pre-boot hooks. Executable files in
/etc/petitboot/boot.d/ are run (in order) before we start the boot
process.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

diff --git a/discover/boot.c b/discover/boot.c
index ae44717523f6df24e36674321186b067023cf65e..8c2e8e19607d1ff056479e084f58c6d958a5be9c 100644 (file)
--- a/discover/boot.c
+++ b/discover/boot.c
@@ -1,6 +1,13 @@
 
 

+#define _GNU_SOURCE
+

 #include <stdbool.h>
 #include <stdbool.h>

+#include <stdlib.h>

 #include <assert.h>
 #include <assert.h>

+#include <dirent.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/types.h>

 
 #include <log/log.h>
 #include <pb-protocol/pb-protocol.h>
 
 #include <log/log.h>
 #include <pb-protocol/pb-protocol.h>


@@ -13,6 +20,8 @@
 #include "paths.h"
 #include "resource.h"
 
 #include "paths.h"
 #include "resource.h"
 

+static const char *boot_hook_dir = PKG_SYSCONF_DIR "/boot.d";
+

 struct boot_task {
        char *local_image;
        char *local_initrd;
 struct boot_task {
        char *local_image;
        char *local_initrd;


@@ -139,6 +148,58 @@ static void update_status(boot_status_fn fn, void *arg, int type,
        fn(arg, &status);
 }
 
        fn(arg, &status);
 }
 

+static int hook_filter(const struct dirent *dirent)
+{
+       return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
+}
+
+static int hook_cmp(const struct dirent **a, const struct dirent **b)
+{
+       return strcmp((*a)->d_name, (*b)->d_name);
+}
+
+static void run_boot_hooks(void *ctx, struct boot_task *task,
+               boot_status_fn status_fn, void *status_arg)
+{
+       struct dirent **hooks;
+       int i, n;
+
+       n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
+       if (n < 1)
+               return;
+
+       update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+                       "running boot hooks");
+
+       /* pass boot data to hooks */
+       setenv("boot_image", task->local_image, 1);
+       if (task->local_initrd)
+               setenv("boot_initrd", task->local_initrd, 1);
+       if (task->local_dtb)
+               setenv("boot_dtb", task->local_dtb, 1);
+       if (task->args)
+               setenv("boot_args", task->args, 1);
+
+       for (i = 0; i < n; i++) {
+               char *path;
+               const char *argv[2] = { NULL, NULL };
+
+               path = join_paths(ctx, boot_hook_dir, hooks[i]->d_name);
+
+               if (access(path, X_OK))
+                       continue;
+
+               pb_log("running boot hook %s\n", hooks[i]->d_name);
+
+               argv[0] = path;
+               pb_run_cmd(argv, 1, task->dry_run);
+
+               talloc_free(path);
+       }
+
+       free(hooks);
+}
+

 int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
                int dry_run, boot_status_fn status_fn, void *status_arg)
 {
 int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
                int dry_run, boot_status_fn status_fn, void *status_arg)
 {


@@ -218,6 +279,8 @@ int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
                }
        }
 
                }
        }
 

+       run_boot_hooks(ctx, &boot_task, status_fn, status_arg);
+

        update_status(status_fn, status_arg, BOOT_STATUS_INFO,
                        "performing kexec_load");
 
        update_status(status_fn, status_arg, BOOT_STATUS_INFO,
                        "performing kexec_load");