11:49 a.m.
Also:
* Un-duplicate device detection code by creating a common mapping function.
* Add some more comments.
---
daemon/devsparts.c | 168 ++++++++++++++++++++++++++++++----------------------
1 files changed, 96 insertions(+), 72 deletions(-)
diff --git a/daemon/devsparts.c b/daemon/devsparts.c
index 1970e7d..b89682c 100644
--- a/daemon/devsparts.c
+++ b/daemon/devsparts.c
@@ -29,14 +29,19 @@
#include "daemon.h"
#include "actions.h"
-char **
-do_list_devices (void)
+typedef int (*block_dev_func_t)(const char *dev,
+ char ***r, int *size, int *alloc);
+
+/* Execute a given function for each discovered block device */
+static char**
+foreach_block_device (block_dev_func_t func)
{
char **r = NULL;
int size = 0, alloc = 0;
+
DIR *dir;
struct dirent *d;
- char buf[256];
+ int err = 0;
dir = opendir ("/sys/block");
if (!dir) {
@@ -44,121 +49,140 @@ do_list_devices (void)
return NULL;
}
+ errno = 0;
while ((d = readdir (dir)) != NULL) {
if (strncmp (d->d_name, "sd", 2) == 0 ||
strncmp (d->d_name, "hd", 2) == 0 ||
- strncmp (d->d_name, "vd", 2) == 0) {
- snprintf (buf, sizeof buf, "/dev/%s", d->d_name);
+ strncmp (d->d_name, "vd", 2) == 0 ||
+ strncmp (d->d_name, "sr", 2) == 0) {
+ char dev_path[256];
+ snprintf (dev_path, sizeof dev_path, "/dev/%s", d->d_name);
/* RHBZ#514505: Some versions of qemu <= 0.10 add a
* CD-ROM device even though we didn't request it. Try to
* detect this by seeing if the device contains media.
*/
- int fd = open (buf, O_RDONLY);
+ int fd = open (dev_path, O_RDONLY);
if (fd == -1) {
- perror (buf);
+ perror (dev_path);
continue;
}
close (fd);
- if (add_string (&r, &size, &alloc, buf) == -1) {
- closedir (dir);
- return NULL;
+ /* Call the map function for this device */
+ if((*func)(d->d_name, &r, &size, &alloc) != 0) {
+ err = 1;
+ break;
}
}
}
- if (add_string (&r, &size, &alloc, NULL) == -1) {
- closedir (dir);
+ /* Check readdir didn't fail */
+ if(0 != errno) {
+ reply_with_perror ("readdir: /sys/block");
+ free_stringslen(r, size);
return NULL;
}
+ /* Close the directory handle */
if (closedir (dir) == -1) {
reply_with_perror ("closedir: /sys/block");
- free_strings (r);
+ free_stringslen(r, size);
+ return NULL;
+ }
+
+ /* Free the result list on error */
+ if(err) {
+ free_stringslen(r, size);
+ return NULL;
+ }
+
+ /* Sort the devices */
+ sort_strings (r, size);
+
+ /* NULL terminate the list */
+ if (add_string (&r, &size, &alloc, NULL) == -1) {
return NULL;
}
- sort_strings (r, size-1);
return r;
}
-char **
-do_list_partitions (void)
+/* Add a device to the list of devices */
+static int
+add_device(const char *device,
+ char ***const r, int *const size, int *const alloc)
{
- char **r = NULL;
- int size = 0, alloc = 0;
- DIR *dir, *dir2;
- struct dirent *d;
- char buf[256], devname[256];
+ char dev_path[256];
+ snprintf (dev_path, sizeof dev_path, "/dev/%s", device);
- dir = opendir ("/sys/block");
- if (!dir) {
- reply_with_perror ("opendir: /sys/block");
- return NULL;
+ if (add_string (r, size, alloc, dev_path) == -1) {
+ return -1;
}
- while ((d = readdir (dir)) != NULL) {
- if (strncmp (d->d_name, "sd", 2) == 0 ||
- strncmp (d->d_name, "hd", 2) == 0 ||
- strncmp (d->d_name, "vd", 2) == 0) {
- snprintf (buf, sizeof buf, "/dev/%s", d->d_name);
+ return 0;
+}
- /* RHBZ#514505: Some versions of qemu <= 0.10 add a
- * CD-ROM device even though we didn't request it. Try to
- * detect this by seeing if the device contains media.
- */
- int fd = open (buf, O_RDONLY);
- if (fd == -1) {
- perror (buf);
- continue;
- }
- close (fd);
+char **
+do_list_devices (void)
+{
+ return foreach_block_device(add_device);
+}
- strncpy (devname, d->d_name, sizeof devname);
- devname[sizeof devname - 1] = '\0';
+static int
+add_partitions(const char *device,
+ char ***const r, int *const size, int *const alloc)
+{
+ char devdir[256];
- snprintf (buf, sizeof buf, "/sys/block/%s", devname);
+ /* Open the device's directory under /sys/block */
+ snprintf (devdir, sizeof devdir, "/sys/block/%s", device);
- dir2 = opendir (buf);
- if (!dir2) {
- reply_with_perror ("opendir: %s", buf);
- free_stringslen (r, size);
- return NULL;
- }
- while ((d = readdir (dir2)) != NULL) {
- if (strncmp (d->d_name, devname, strlen (devname)) == 0) {
- snprintf (buf, sizeof buf, "/dev/%s", d->d_name);
-
- if (add_string (&r, &size, &alloc, buf) == -1) {
- closedir (dir2);
- closedir (dir);
- return NULL;
- }
- }
- }
+ DIR *dir = opendir (devdir);
+ if (!dir) {
+ reply_with_perror ("opendir: %s", devdir);
+ free_stringslen (*r, *size);
+ return -1;
+ }
- if (closedir (dir2) == -1) {
- reply_with_perror ("closedir: /sys/block/%s", devname);
- free_stringslen (r, size);
- return NULL;
+ /* Look in /sys/block/<device>/ for entries starting with <device>
+ * e.g. /sys/block/sda/sda1
+ */
+ errno = 0;
+ struct dirent *d;
+ while ((d = readdir (dir)) != NULL) {
+ if (strncmp (d->d_name, device, strlen (device)) == 0) {
+ char part[256];
+ snprintf (part, sizeof part, "/dev/%s", d->d_name);
+
+ if (add_string (r, size, alloc, part) == -1) {
+ closedir (dir);
+ return -1;
}
}
}
- if (add_string (&r, &size, &alloc, NULL) == -1) {
- closedir (dir);
- return NULL;
+ /* Check if readdir failed */
+ if(0 != errno) {
+ reply_with_perror ("readdir: %s", devdir);
+ free_stringslen(*r, *size);
+ return -1;
}
+ /* Close the directory handle */
if (closedir (dir) == -1) {
- reply_with_perror ("closedir: /sys/block");
- free_strings (r);
- return NULL;
+ reply_with_perror ("closedir: /sys/block/%s", device);
+ free_stringslen (*r, *size);
+ return -1;
}
- sort_strings (r, size-1);
- return r;
+ return 0;
+}
+
+char **
+do_list_partitions (void)
+{
+ return foreach_block_device(add_partitions);
}
int
--
1.6.2.5