diff options
| -rw-r--r-- | lib/configfs.c | 58 |
1 files changed, 54 insertions, 4 deletions
diff --git a/lib/configfs.c b/lib/configfs.c index 0a8d8e5..56bff01 100644 --- a/lib/configfs.c +++ b/lib/configfs.c @@ -399,6 +399,46 @@ static int parse_legacy_g_webcam(const char *udc, */ /* + * configfs_mount_point - Identify the ConfigFS mount location + * + * Return a pointer to a newly allocated string containing the fully qualified + * path to the ConfigFS mount point if located. Returns NULL if the ConfigFS + * mount point can not be identified. + */ +static char *configfs_mount_point(void) +{ + FILE *mounts; + char *line = NULL; + char *path = NULL; + size_t len = 0; + + mounts = fopen("/proc/mounts", "r"); + if (mounts == NULL) + return NULL; + + while (getline(&line, &len, mounts) != -1) { + if (strstr(line, "configfs")) { + char *saveptr; + char *token; + + /* Obtain the second token. */ + token = strtok_r(line, " ", &saveptr); + token = strtok_r(NULL, " ", &saveptr); + + if (token) + path = strdup(token); + + break; + } + } + + free(line); + fclose(mounts); + + return path; +} + +/* * configfs_find_uvc_function - Find the ConfigFS full path for a UVC function * @function: The UVC function name * @@ -409,9 +449,15 @@ static int parse_legacy_g_webcam(const char *udc, static char *configfs_find_uvc_function(const char *function) { const char *target = function ? function : "*"; - const char *root; + const char *format; + char *configfs; char *func_path; char *path; + int ret; + + configfs = configfs_mount_point(); + if (!configfs) + printf("Failed to locate configfs mount point, using default\n"); /* * The function description can be provided as a path from the @@ -419,11 +465,15 @@ static char *configfs_find_uvc_function(const char *function) * over the gadget name, a shortcut "uvc.0" can be provided. */ if (!strchr(target, '/')) - root = "/sys/kernel/config/usb_gadget/*/functions"; + format = "%s/usb_gadget/*/functions/%s"; else - root = "/sys/kernel/config/usb_gadget"; + format = "%s/usb_gadget/%s"; - path = path_join(root, target); + ret = asprintf(&path, format, configfs ? configfs : "/sys/kernel/config", + target); + free(configfs); + if (!ret) + return NULL; func_path = path_glob_first_match(path); free(path); |