Add fundamental list functions to manage log devices

This commit does the below things:
* Add fundamental list functions to manage log devices
* Fix a issue that if both log system and log apps are available, the
  latter will overwrite the devices->next!
* release memory at exit

Change-Id: Iebc3f8d2b34d6abbd834b07a31e0c2ebba01b63b
Signed-off-by: Chengwei Yang <chengwei.yang@intel.com>

diff --git a/logutil.c b/logutil.c
index cf544d8..671efee 100755 (executable)
--- a/logutil.c
+++ b/logutil.c
@@ -430,6 +430,97 @@ static void show_help(const char *cmd)
 }
 
 
+/*
+ * free one log_device_t and it doesn't take care of chain so it
+ * may break the chain list
+ */
+static void log_devices_free(struct log_device_t *dev)
+{
+       if (!dev)
+               return;
+
+       if (dev->device)
+               free(dev->device);
+
+       if (dev->queue) {
+               while (dev->queue->next) {
+                       struct queued_entry_t *tmp = dev->queue->next;
+                       dev->queue->next = tmp->next;
+                       free(tmp);
+               }
+               free(dev->queue);
+       }
+
+       free(dev);
+       dev = NULL;
+}
+
+
+/*
+ * free all the nodes after the "dev" and includes itself
+ */
+static void log_devices_chain_free(struct log_device_t *dev)
+{
+       if (!dev)
+               return;
+
+       while (dev->next) {
+               struct log_device_t *tmp = dev->next;
+               dev->next = tmp->next;
+               log_devices_free(tmp);
+       }
+
+       log_devices_free(dev);
+       dev = NULL;
+}
+
+
+/*
+ * create a new log_device_t instance but don't care about
+ * the device node accessable or not
+ */
+static struct log_device_t *log_devices_new(const char *path)
+{
+       struct log_device_t *new;
+
+       if (!path || strlen(path) <= 0)
+               return NULL;
+
+       new = malloc(sizeof(*new));
+       if (!new) {
+               fprintf(stderr, "out of memory\n");
+               return NULL;
+       }
+
+       new->device = strdup(path);
+       new->fd = -1;
+       new->printed = false;
+       new->queue = NULL;
+       new->next = NULL;
+
+       return new;
+}
+
+
+/*
+ * add a new device to the tail of chain
+ */
+static int log_devices_add_to_tail(struct log_device_t *devices, struct log_device_t *new)
+{
+       struct log_device_t *tail = devices;
+
+       if (!devices || !new)
+               return -1;
+
+       while (tail->next)
+               tail = tail->next;
+
+       tail->next = new;
+       g_dev_count++;
+
+       return 0;
+}
+
 int main(int argc, char **argv)
 {
     int err;
@@ -489,44 +580,22 @@ int main(int argc, char **argv)
             break;
 
                        case 'b': {
-                                                 char* buf = (char*) malloc(strlen(LOG_FILE_DIR) + strlen(optarg) + 1);
-                                                 if (buf == NULL) {
-                                                         fprintf(stderr,"Can't malloc LOG_FILE_DIR\n");
+                                                 char *buf;
+                                                 if (asprintf(&buf, LOG_FILE_DIR "/%s", optarg) == -1) {
+                                                         asprintf(stderr,"Can't malloc LOG_FILE_DIR\n");
                                                          exit(-1);
                                                  }
-                                                 strcpy(buf, LOG_FILE_DIR);
-                                                 strcat(buf, optarg);
-                                                 //            snprintf(buf, strlen(LOG_FILE_DIR) + strlen(optarg) + 1, "%s%s", LOG_FILE_DIR, optarg);
 
+                                                 dev = log_devices_new(buf);
                 if (devices) {
-                                       dev = devices;
-                    while (dev->next) {
-                                               dev = dev->next;
-                                       }
-                                       dev->next = (struct log_device_t *)malloc( sizeof(struct log_device_t));
-                                       if (dev->next == NULL) {
-                                               fprintf(stderr,"Can't malloc log_device\n");
+                                       if (log_devices_add_to_tail(devices, dev)) {
+                                               fprintf(stderr, "Open log device %s failed\n", buf);
                                                exit(-1);
                                        }
-                                       dev->next->device = buf;
-                                       dev->next->fd = -1;
-                                       dev->next->printed = false;
-                                       dev->next->queue = NULL;
-                                       dev->next->next = NULL;
-
                 } else {
-                                       devices = (struct log_device_t *)malloc( sizeof(struct log_device_t));
-                                       if (devices == NULL) {
-                                               fprintf(stderr,"Can't malloc log_device\n");
-                                               exit(-1);
-                                       }
-                                       devices->device = buf;
-                                       devices->fd = -1;
-                                       devices->printed = false;
-                                       devices->queue = NULL;
-                                       devices->next = NULL;
+                                       devices = dev;
+                                       g_dev_count = 1;
                 }
-                g_dev_count++;
             }
             break;
 
@@ -584,49 +653,30 @@ int main(int argc, char **argv)
        }
 
        if (!devices) {
-        devices = (struct log_device_t *)malloc( sizeof(struct log_device_t));
+               devices = log_devices_new("/dev/"LOGGER_LOG_MAIN);
                if (devices == NULL) {
-                       fprintf(stderr,"Can't malloc log_device\n");
+                       fprintf(stderr,"Can't add log device: %s\n", LOGGER_LOG_MAIN);
                        exit(-1);
                }
-               devices->device = strdup("/dev/"LOGGER_LOG_MAIN);
-               devices->fd = -1;
-               devices->printed = false;
-               devices->queue = NULL;
-               devices->next = NULL;
         g_dev_count = 1;
 
-
         int accessmode =
                   (mode & O_RDONLY) ? R_OK : 0
                 | (mode & O_WRONLY) ? W_OK : 0;
 
-        // only add this if it's available
+       // only add this if it's available
        if (0 == access("/dev/"LOGGER_LOG_SYSTEM, accessmode)) {
-               devices->next = (struct log_device_t *)malloc( sizeof(struct log_device_t));
-               if (devices->next == NULL) {
-                       fprintf(stderr,"Can't malloc log_device\n");
+               if (log_devices_add_to_tail(devices, log_devices_new("/dev/"LOGGER_LOG_SYSTEM))) {
+                       fprintf(stderr,"Can't add log device: %s\n", LOGGER_LOG_SYSTEM);
                        exit(-1);
                }
-               devices->next->device = strdup("/dev/"LOGGER_LOG_SYSTEM);
-               devices->next->fd = -1;
-               devices->next->printed = false;
-               devices->next->queue = NULL;
-               devices->next->next = NULL;
-               g_dev_count ++;
        }
+
        if (0 == access("/dev/"LOGGER_LOG_APPS, accessmode)) {
-               devices->next = (struct log_device_t *)malloc( sizeof(struct log_device_t));
-               if (devices->next == NULL) {
-                       fprintf(stderr,"Can't malloc log_device\n");
+               if (log_devices_add_to_tail(devices, log_devices_new("/dev/"LOGGER_LOG_APPS))) {
+                       fprintf(stderr,"Can't add log device: %s\n", LOGGER_LOG_APPS);
                        exit(-1);
                }
-               devices->next->device = strdup("/dev/"LOGGER_LOG_APPS);
-               devices->next->fd = -1;
-               devices->next->printed = false;
-               devices->next->queue = NULL;
-               devices->next->next = NULL;
-               g_dev_count ++;
        }
 /*
         // only add this if it's available
@@ -767,5 +817,7 @@ int main(int argc, char **argv)
 
     read_log_lines(devices);
 
+       log_devices_chain_free(devices);
+
     return 0;
 }