REFACTOR: refactor config file support for server configuration

Author: singsangssong

config_parser.c

@@ -26,9 +26,6 @@
 #include <memcached/config_parser.h>
 #include <memcached/util.h>
 
-static int read_config_file(const char *fname, struct config_item items[],
-                            FILE *error);
-
 /**
  * Copy a string and trim of leading and trailing white space characters.
  * Allow the user to escape out the stop character by putting a backslash before
@@ -224,8 +221,8 @@ int parse_config(const char *str, struct config_item *items, FILE *error) {
    return ret;
 }
 
-static int read_config_file(const char *fname, struct config_item items[],
-                            FILE *error) {
+int read_config_file(const char *fname, struct config_item items[],
+                     FILE *error) {
    FILE *fp = fopen(fname, "r");
    if (fp == NULL) {
       (void)fprintf(error, "Failed to open file: %s\n", fname);

include/memcached/config_parser.h

@@ -77,6 +77,7 @@ struct config_item {
  */
 MEMCACHED_PUBLIC_API int parse_config(const char *str, struct config_item items[], FILE *error);
 
+int read_config_file(const char *fname, struct config_item items[], FILE *error);
 #ifdef __cplusplus
 }
 #endif

memcached.c

@@ -15804,6 +15804,83 @@ static bool sanitycheck(void)
     return true;
 }
 
+static int try_load_config_file(const char *path,
+                                char **username_ptr,
+                                char **pid_file_ptr,
+                                const char **engine_ptr,
+                                bool *lock_memory_ptr,
+                                bool *do_daemonize_ptr,
+                                int *maxcore_ptr
+#ifdef ENABLE_ZK_INTEGRATION
+                                , int *arcus_zk_to_ptr
+#endif
+                                )
+{
+    char *access_mask_str = NULL;
+    char *protocol_str = NULL;
+
+    struct config_item main_config_items[] = {
+        { .key = "port",          .datatype = DT_UINT32, .value.dt_uint32 = (uint32_t*)&settings.port },
+        { .key = "udpport",       .datatype = DT_UINT32, .value.dt_uint32 = (uint32_t*)&settings.udpport },
+        { .key = "socketpath",    .datatype = DT_STRING, .value.dt_string = &settings.socketpath },
+        { .key = "access",        .datatype = DT_STRING, .value.dt_string = &access_mask_str },
+        { .key = "listen",        .datatype = DT_STRING, .value.dt_string = &settings.inter },
+        { .key = "daemonize",     .datatype = DT_BOOL,   .value.dt_bool = do_daemonize_ptr },
+        { .key = "maxcore",       .datatype = DT_BOOL,   .value.dt_bool = (bool*)&maxcore_ptr },
+        { .key = "username",      .datatype = DT_STRING, .value.dt_string = username_ptr },
+        { .key = "maxconns",      .datatype = DT_UINT32, .value.dt_uint32 = (uint32_t*)&settings.maxconns },
+        { .key = "lock_memory",   .datatype = DT_BOOL,   .value.dt_bool = lock_memory_ptr },
+        { .key = "verbosity",     .datatype = DT_SIZE,   .value.dt_size   = (size_t*)&settings.verbose },
+        { .key = "pid_file",      .datatype = DT_STRING, .value.dt_string = pid_file_ptr },
+        { .key = "threads",       .datatype = DT_UINT32, .value.dt_uint32 = (uint32_t*)&settings.num_threads },
+        { .key = "reqs_per_event", .datatype = DT_UINT32, .value.dt_uint32 = (uint32_t*)&settings.reqs_per_event },
+        { .key = "backlog",       .datatype = DT_UINT32, .value.dt_uint32 = (uint32_t*)&settings.backlog },
+        { .key = "protocol",      .datatype = DT_STRING, .value.dt_string = &protocol_str },
+        { .key = "engine_path", .datatype = DT_STRING, .value.dt_string = (char**)&engine_ptr },
+
+        { .key = "memory_limit",  .datatype = DT_SIZE,   .value.dt_size   = &settings.maxbytes },
+        { .key = "eviction",      .datatype = DT_BOOL,   .value.dt_bool   = (bool*)&settings.evict_to_free },
+        { .key = "sticky_limit",  .datatype = DT_SIZE,   .value.dt_size   = &settings.sticky_limit },
+        { .key = "factor",        .datatype = DT_FLOAT,  .value.dt_float  = (float*)&settings.factor },
+        { .key = "chunk_size",    .datatype = DT_SIZE,   .value.dt_size   = (size_t*)&settings.chunk_size },
+        { .key = "prefix_delimiter", .datatype = DT_CHAR, .value.dt_char = &settings.prefix_delimiter},
+        { .key = "use_cas",       .datatype = DT_BOOL,   .value.dt_bool   = &settings.use_cas },
+        { .key = "item_size_max", .datatype = DT_SIZE,   .value.dt_size   = &settings.item_size_max },
+
+#ifdef ENABLE_ZK_INTEGRATION
+        { .key = "zookeeper",   .datatype = DT_STRING, .value.dt_string = (char**)&arcus_zk_cfg },
+        { .key = "zk_timeout",  .datatype = DT_UINT32, .value.dt_uint32 = (uint32_t*)&arcus_zk_to },
+#endif
+        { .key = NULL}
+    };
+
+    if (read_config_file(path, main_config_items, stderr) == -1) {
+        fprintf(stderr, "Error parsing config file. Aborting.\n");
+        return -1;
+    }
+
+    if (access_mask_str != NULL) {
+        settings.access = strtol(access_mask_str, NULL, 8);
+        free(access_mask_str);
+    }
+    if (protocol_str != NULL) {
+        if (strcmp(protocol_str, "auto") == 0) {
+            settings.binding_protocol = negotiating_prot;
+        } else if (strcmp(protocol_str, "binary") == 0) {
+            settings.binding_protocol = binary_prot;
+        } else if (strcmp(protocol_str, "ascii") == 0) {
+            settings.binding_protocol = ascii_prot;
+        } else {
+            fprintf(stderr, "Invalid value for binding protocol in config file: %s\n", protocol_str);
+            free(protocol_str);
+            return -1;
+        }
+        free(protocol_str);
+    }
+
+    return 0;
+}
+
 static void settings_reload_engine_config(void)
 {
     ENGINE_ERROR_CODE ret;
@@ -15898,6 +15975,30 @@ int main (int argc, char **argv)
         return EX_OSERR;
     }
 
+    /* parse config file */
+    if (argc > 1 && argv[1][0] != '-') {
+        const char *config_file = argv[1];
+
+        if (try_load_config_file(config_file,
+                                 &username,
+                                 &pid_file,
+                                 &engine,
+                                 &lock_memory,
+                                 &do_daemonize,
+                                 &maxcore
+#ifdef ENABLE_ZK_INTEGRATION
+                                 , &arcus_zk_to
+#endif
+                                 ) != 0) {
+            fprintf(stderr, "Error parsing config file '%s'.", config_file);
+            exit(EXIT_FAILURE);
+        }
+
+        optind = 2;
+    } else {
+        optind = 1;
+    }
+
     /* process arguments */
     while (-1 != (c = getopt(argc, argv,
           "a:"  /* access mask for unix socket */