Simplify list command

Use scandir with an appropriate filter to find all our nvme namespaces
and handle allocating all the dirent's. Makes the implementation a
little simpler.

Signed-off-by: Keith Busch <keith.busch@intel.com>

diff --git a/nvme.c b/nvme.c
index 1bd74fd6cd8530d66fe55c9c84e06766916460ce..636053d9c1c698f8a262985ef118523bc8f298a3 100644 (file)
--- a/nvme.c
+++ b/nvme.c
@@ -772,70 +772,55 @@ static int get_nvme_info(int fd, struct list_item *item, const char *node)
 }
 
 static const char *dev = "/dev/";
-static int list(int argc, char **argv, struct command *cmd, struct plugin *plugin)
+
+/* Assume every block device starting with /dev/nvme is an nvme namespace */
+static int scan_dev_filter(const struct dirent *d)
 {
-       DIR *d;
-       struct dirent *entry;
-       char path[256] = { 0 };
-       struct list_item list_items[MAX_LIST_ITEMS];
+       char path[256];
        struct stat bd;
-       unsigned int count = 0;
-       int ret;
 
-       d = opendir(dev);
-       if (!d) {
-               fprintf(stderr,
-                       "Failed to open directory %s with error %s\n",
-                       dev, strerror(errno));
-               return errno;
+       if (d->d_name[0] == '.')
+               return 0;
+
+       if (strstr(d->d_name, "nvme")) {
+               snprintf(path, sizeof(path), "%s%s", dev, d->d_name);
+               if (stat(path, &bd))
+                       return 0;
+               if (S_ISBLK(bd.st_mode))
+                       return 1;
        }
+       return 0;
+}
 
-       while (1) {
-               errno = 0;
-               entry = readdir(d);
-               if (NULL == entry) {
-                       /* Error while reading directory */
-                       if (errno) {
-                               fprintf(stderr,
-                                               "Failed to read contents of %s with error %s\n",
-                                               dev, strerror(errno));
-                               closedir(d);
-                               return errno;
-                       }
-                       else {
-                               /* done reading the directory stream */
-                               break;
-                       }
-               }
-               /* lets not walk the entire fs */
-               if (!strcmp(entry->d_name, ".."))
-                       continue;
-               if (strstr(entry->d_name, "nvme") != NULL) {
-                       snprintf(path, sizeof(path), "%s%s", dev, entry->d_name);
-                       if (stat(path, &bd)) {
-                               fprintf(stderr,
-                                               "Failed to stat %s with error %s\n",
-                                               path, strerror(errno));
-                               closedir(d);
-                               return errno;
-                       }
-                       if (S_ISBLK(bd.st_mode)) {
-                               open_dev(path);
-                               ret = get_nvme_info(fd, &list_items[count], path);
-                               if (ret > 0) {
-                                       closedir(d);
-                                       return ret;
-                               }
-                               count++;
-                       }
-               }
+static int list(int argc, char **argv, struct command *cmd, struct plugin *plugin)
+{
+       char path[256];
+       struct dirent **devices;
+       struct list_item *list_items;
+       unsigned int i, n, fd, ret;
+
+       n = scandir(dev, &devices, scan_dev_filter, alphasort);
+       if (n <= 0)
+               return n;
+
+       list_items = calloc(n, sizeof(*list_items));
+       if (!list_items)
+               return ENOMEM;
+
+       for (i = 0; i < n; i++) {
+               snprintf(path, sizeof(path), "%s%s", dev, devices[i]->d_name);
+               fd = open(path, O_RDONLY);
+               ret = get_nvme_info(fd, &list_items[i], path);
+               if (ret)
+                       return ret;
        }
-       closedir(d);
+       print_list_items(list_items, n);
+
+       for (i = 0; i < n; i++)
+               free(devices[i]);
+       free(devices);
+       free(list_items);
 
-       if (count)
-               print_list_items(list_items, count);
-       else
-               printf("No NVMe devices detected.\n");
        return 0;
 }