Finished writing the code to generate Subsonic LinkTable

- Also refactored various bits and pieces

Makefile

@@ -1,7 +1,8 @@
 VERSION=1.1.10
 
-CFLAGS+= -O2 -Wall -Wextra -Wshadow -rdynamic\
+CFLAGS+= -O2 -Wall -Wextra -Wshadow\
-	-D_FILE_OFFSET_BITS=64 -DVERSION=\"$(VERSION)\" \
+	-rdynamic -D_XOPEN_SOURCE=700 -D_DEFAULT_SOURCE\
+	-D_FILE_OFFSET_BITS=64 -DVERSION=\"$(VERSION)\"\
 	`pkg-config --cflags-only-I gumbo libcurl fuse uuid expat`
 LIBS = -pthread -lgumbo -lcurl -lfuse -lcrypto -luuid -lexpat
 COBJS = network.o fuse_local.o link.o cache.o util.o main.o

src/cache.c

@@ -9,21 +9,6 @@
 #include <string.h>
 #include <unistd.h>
 
-/**
- * \brief Data file block size
- * \details We set it to 1024*1024*8 = 8MiB
- */
-
-#define DEFAULT_DATA_BLK_SZ         8*1024*1024
-
-/**
- * \brief Maximum segment block count
- * \details This is set to 128*1024 blocks, which uses 128KB. By default,
- * this allows the user to store (128*1024)*(8*1024*1024) = 1TB of data
- */
-
-#define DEFAULT_MAX_SEGBC                   128*1024
-
 /**
  * \brief error associated with metadata
  */
@@ -36,10 +21,7 @@ typedef enum {
 } MetaError;
 
 /* ---------------- External variables -----------------------*/
-
 int CACHE_SYSTEM_INIT = 0;
-int DATA_BLK_SZ = 0;
-int MAX_SEGBC = DEFAULT_MAX_SEGBC;
 char *META_DIR;
 
 /* ----------------- Static variables ----------------------- */
@@ -156,10 +138,6 @@ void CacheSystem_init(const char *path, int url_supplied)
                 strerror(errno));
     }
 
-    if (!DATA_BLK_SZ) {
-        DATA_BLK_SZ = DEFAULT_DATA_BLK_SZ;
-    }
-
     CACHE_SYSTEM_INIT = 1;
 }
 
@@ -202,12 +180,12 @@ blksz: %d, segbc: %ld\n", cf->path, cf->content_length, cf->blksz, cf->segbc);
         return EZERO;
     }
 
-    if (cf->blksz != DATA_BLK_SZ) {
+    if (cf->blksz != CONFIG.data_blksz) {
-        fprintf(stderr, "Meta_read(): Warning: cf->blksz != DATA_BLK_SZ\n");
+        fprintf(stderr, "Meta_read(): Warning: cf->blksz != CONFIG.data_blksz\n");
     }
 
     /* Allocate some memory for the segment */
-    if (cf->segbc > MAX_SEGBC) {
+    if (cf->segbc > CONFIG.max_segbc) {
         fprintf(stderr, "Meta_read(): Error: segbc: %ld\n", cf->segbc);
         return EMEM;
     }
@@ -671,7 +649,7 @@ int Cache_create(Link *this_link)
     cf->path = strndup(fn, MAX_PATH_LEN);
     cf->time = this_link->time;
     cf->content_length = this_link->content_length;
-    cf->blksz = DATA_BLK_SZ;
+    cf->blksz = CONFIG.data_blksz;
     cf->segbc = (cf->content_length / cf->blksz) + 1;
     cf->seg = CALLOC(cf->segbc, sizeof(Seg));
 

src/cache.h

@@ -70,16 +70,6 @@ struct Cache {
  */
 extern int CACHE_SYSTEM_INIT;
 
-/**
- * \brief The size of each download segment
- */
-extern int DATA_BLK_SZ;
-
-/**
- * \brief The maximum segment count for a single cache file
- */
-extern int MAX_SEGBC;
-
 /**
  * \brief The metadata directory
  */

src/link.c

@@ -49,9 +49,9 @@ LinkTable *LinkSystem_init(const char *url)
     }
 
     /* -----------  Enable cache system --------------------*/
-    if (NETWORK_CONFIG.cache_enabled) {
+    if (CONFIG.cache_enabled) {
-        if (NETWORK_CONFIG.cache_dir) {
+        if (CONFIG.cache_dir) {
-            CacheSystem_init(NETWORK_CONFIG.cache_dir, 0);
+            CacheSystem_init(CONFIG.cache_dir, 0);
         } else {
             CacheSystem_init(url, 1);
         }
@@ -62,7 +62,7 @@ LinkTable *LinkSystem_init(const char *url)
     return ROOT_LINK_TBL;
 }
 
-static void LinkTable_add(LinkTable *linktbl, Link *link)
+void LinkTable_add(LinkTable *linktbl, Link *link)
 {
     linktbl->num++;
     linktbl->links = realloc(linktbl->links, linktbl->num * sizeof(Link *));
@@ -139,7 +139,7 @@ static CURL *Link_to_curl(Link *link)
         fprintf(stderr, "Link_to_curl(): curl_easy_init() failed!\n");
     }
     /* set up some basic curl stuff */
-    curl_easy_setopt(curl, CURLOPT_USERAGENT, NETWORK_CONFIG.user_agent);
+    curl_easy_setopt(curl, CURLOPT_USERAGENT, CONFIG.user_agent);
     curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
     /* for following directories without the '/' */
     curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 2);
@@ -151,26 +151,26 @@ static CURL *Link_to_curl(Link *link)
 
 //     curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
 
-    if (NETWORK_CONFIG.username) {
+    if (CONFIG.http_username) {
-        curl_easy_setopt(curl, CURLOPT_USERNAME, NETWORK_CONFIG.username);
+        curl_easy_setopt(curl, CURLOPT_USERNAME, CONFIG.http_username);
     }
 
-    if (NETWORK_CONFIG.password) {
+    if (CONFIG.http_password) {
-        curl_easy_setopt(curl, CURLOPT_PASSWORD, NETWORK_CONFIG.password);
+        curl_easy_setopt(curl, CURLOPT_PASSWORD, CONFIG.http_password);
     }
 
-    if (NETWORK_CONFIG.proxy) {
+    if (CONFIG.proxy) {
-        curl_easy_setopt(curl, CURLOPT_PROXY, NETWORK_CONFIG.proxy);
+        curl_easy_setopt(curl, CURLOPT_PROXY, CONFIG.proxy);
     }
 
-    if (NETWORK_CONFIG.proxy_user) {
+    if (CONFIG.proxy_username) {
         curl_easy_setopt(curl, CURLOPT_PROXYUSERNAME,
-                         NETWORK_CONFIG.proxy_user);
+                         CONFIG.proxy_username);
     }
 
-    if (NETWORK_CONFIG.proxy_pass) {
+    if (CONFIG.proxy_password) {
         curl_easy_setopt(curl, CURLOPT_PROXYPASSWORD,
-                         NETWORK_CONFIG.proxy_pass);
+                         CONFIG.proxy_password);
     }
 
     return curl;
@@ -355,7 +355,7 @@ DataStruct Link_to_DataStruct(Link *head_link)
             fprintf(stderr,
                     "LinkTable_new(): URL: %s, HTTP %ld, retrying later.\n",
                     url, http_resp);
-            sleep(HTTP_WAIT_SEC);
+            sleep(CONFIG.http_wait_sec);
         } else if (http_resp != HTTP_OK) {
             fprintf(stderr,
                     "LinkTable_new(): cannot retrieve URL: %s, HTTP %ld\n",

src/link.h

@@ -159,4 +159,8 @@ void LinkTable_free(LinkTable *linktbl);
  */
 void LinkTable_print(LinkTable *linktbl);
 
+/**
+ * \brief add a Link to a LinkTable
+ */
+void LinkTable_add(LinkTable *linktbl, Link *link);
 #endif

src/main.c

@@ -36,7 +36,7 @@ int main(int argc, char **argv)
     add_arg(&fuse_argv, &fuse_argc, argv[0]);
 
     /* initialise network configuration struct */
-    NetworkConfig_init();
+    Config_init();
 
     /* initialise network subsystem */
     NetworkSystem_init();
@@ -140,7 +140,10 @@ parse_arg_list(int argc, char **argv, char ***fuse_argv, int *fuse_argc)
         {"max-conns", required_argument, NULL, 'L'},        /* 11 */
         {"user-agent", required_argument, NULL, 'L'},       /* 12 */
         {"retry-wait", required_argument, NULL, 'L'},       /* 13 */
-        {"cache-location", required_argument, NULL, 'L'},    /* 14 */
+        {"cache-location", required_argument, NULL, 'L'},   /* 14 */
+        {"sonic-username", required_argument, NULL, 'L'},   /* 15 */
+        {"sonic-password", required_argument, NULL, 'L'},   /* 16 */
+        {"sonic", no_argument, NULL, 'L'},                  /* 17 */
         {0, 0, 0, 0}
     };
     while ((c =
@@ -170,43 +173,52 @@ parse_arg_list(int argc, char **argv, char ***fuse_argv, int *fuse_argc)
                 add_arg(fuse_argv, fuse_argc, "-s");
                 break;
             case 'u':
-                NETWORK_CONFIG.username = strdup(optarg);
+                CONFIG.http_username = strdup(optarg);
                 break;
             case 'p':
-                NETWORK_CONFIG.password = strdup(optarg);
+                CONFIG.http_password = strdup(optarg);
                 break;
             case 'P':
-                NETWORK_CONFIG.proxy = strdup(optarg);
+                CONFIG.proxy = strdup(optarg);
                 break;
             case 'L':
                 /* Long options */
                 switch (long_index) {
                     case 6:
-                        NETWORK_CONFIG.proxy_user = strdup(optarg);
+                        CONFIG.proxy_username = strdup(optarg);
                         break;
                     case 7:
-                        NETWORK_CONFIG.proxy_pass = strdup(optarg);
+                        CONFIG.proxy_password = strdup(optarg);
                         break;
                     case 8:
-                        NETWORK_CONFIG.cache_enabled = 1;
+                        CONFIG.cache_enabled = 1;
                         break;
                     case 9:
-                        DATA_BLK_SZ = atoi(optarg) * 1024 * 1024;
+                        CONFIG.data_blksz = atoi(optarg) * 1024 * 1024;
                         break;
                     case 10:
-                        MAX_SEGBC = atoi(optarg);
+                        CONFIG.max_segbc = atoi(optarg);
                         break;
                     case 11:
-                        NETWORK_CONFIG.max_conns = atoi(optarg);
+                        CONFIG.max_conns = atoi(optarg);
                         break;
                     case 12:
-                        NETWORK_CONFIG.user_agent = strdup(optarg);
+                        CONFIG.user_agent = strdup(optarg);
                         break;
                     case 13:
-                        HTTP_WAIT_SEC = atoi(optarg);
+                        CONFIG.http_wait_sec = atoi(optarg);
                         break;
                     case 14:
-                        NETWORK_CONFIG.cache_dir = strdup(optarg);
+                        CONFIG.cache_dir = strdup(optarg);
+                        break;
+                    case 15:
+                        CONFIG.sonic_username = strdup(optarg);
+                        break;
+                    case 16:
+                        CONFIG.sonic_password = strdup(optarg);
+                        break;
+                    case 17:
+                        CONFIG.sonic_mode = 1;
                         break;
                     default:
                         fprintf(stderr, "see httpdirfs -h for usage\n");

src/network.c

@@ -9,13 +9,9 @@
 #include <stdio.h>
 #include <unistd.h>
 
-#define DEFAULT_NETWORK_MAX_CONNS   10
-#define DEFAULT_HTTP_WAIT_SEC       5
 
 /* ----------------- External variables ---------------------- */
 CURLSH *CURL_SHARE;
-NetworkConfigStruct NETWORK_CONFIG;
-int HTTP_WAIT_SEC = DEFAULT_HTTP_WAIT_SEC;
 
 /* ----------------- Static variable ----------------------- */
 /** \brief curl multi interface handle */
@@ -123,8 +119,8 @@ static void curl_process_msgs(CURLMsg *curl_msg, int n_running_curl,
             if (!slept) {
                 fprintf(stderr,
                         "curl_process_msgs(): HTTP %ld, sleeping for %d sec\n",
-                        http_resp, HTTP_WAIT_SEC);
+                        http_resp, CONFIG.http_wait_sec);
-                sleep(HTTP_WAIT_SEC);
+                sleep(CONFIG.http_wait_sec);
                 slept = 1;
             }
         } else {
@@ -231,19 +227,6 @@ int curl_multi_perform_once(void)
     return n_running_curl;
 }
 
-void NetworkConfig_init(void)
-{
-    NETWORK_CONFIG.username = NULL;
-    NETWORK_CONFIG.password = NULL;
-    NETWORK_CONFIG.proxy = NULL;
-    NETWORK_CONFIG.proxy_user = NULL;
-    NETWORK_CONFIG.proxy_pass = NULL;
-    NETWORK_CONFIG.max_conns = DEFAULT_NETWORK_MAX_CONNS;
-    NETWORK_CONFIG.user_agent = DEFAULT_USER_AGENT;
-    NETWORK_CONFIG.cache_enabled = 0;
-    NETWORK_CONFIG.cache_dir = NULL;
-}
-
 void NetworkSystem_init(void)
 {
     /* ------- Global related ----------*/
@@ -277,9 +260,9 @@ void NetworkSystem_init(void)
         exit_failure();
     }
     curl_multi_setopt(curl_multi, CURLMOPT_MAX_TOTAL_CONNECTIONS,
-                      NETWORK_CONFIG.max_conns);
+                      CONFIG.max_conns);
     curl_multi_setopt(curl_multi, CURLMOPT_MAX_HOST_CONNECTIONS,
-                      NETWORK_CONFIG.max_conns);
+                      CONFIG.max_conns);
 
     /* ------------ Initialise locks ---------*/
     if (pthread_mutex_init(&transfer_lock, NULL)) {

src/network.h

@@ -8,24 +8,6 @@
 
 #include "link.h"
 
-/**
- * \brief the default user agent string
- */
-#define DEFAULT_USER_AGENT "HTTPDirFS-" VERSION
-
-typedef struct {
-    char *username;
-    char *password;
-    char *proxy;
-    char *proxy_user;
-    char *proxy_pass;
-    long max_conns;
-    char *user_agent;
-    int http_429_wait;
-    char *cache_dir;
-    int cache_enabled;
-} NetworkConfigStruct;
-
 /** \brief HTTP response codes */
 typedef enum {
     HTTP_OK                         = 200,
@@ -36,21 +18,12 @@ typedef enum {
     HTTP_CLOUDFLARE_TIMEOUT         = 524
 } HTTPResponseCode;
 
-/** \brief The waiting time after getting HTTP 429 */
-extern int HTTP_WAIT_SEC;
-
-/** \brief CURL configuration */
-extern NetworkConfigStruct NETWORK_CONFIG;
-
 /** \brief curl shared interface */
 extern CURLSH *CURL_SHARE;
 
 /** \brief perform one transfer cycle */
 int curl_multi_perform_once(void);
 
-/** \brief initialise network config struct */
-void NetworkConfig_init(void);
-
 /** \brief initialise the network module */
 void NetworkSystem_init(void);
 

src/sonic.c

@@ -8,6 +8,8 @@
 
 #include <string.h>
 #include <stdlib.h>
+#include <unistd.h>
+
 
 typedef struct {
     char *server;
@@ -31,8 +33,8 @@ void sonic_config_init(const char *server, const char *username,
     if (SONIC_CONFIG.server[server_url_len] == '/') {
         SONIC_CONFIG.server[server_url_len] = '\0';
     }
-    SONIC_CONFIG.username = strndup(username, MAX_FILENAME_LEN);
+    SONIC_CONFIG.http_username = strndup(username, MAX_FILENAME_LEN);
-    SONIC_CONFIG.password = strndup(password, MAX_FILENAME_LEN);
+    SONIC_CONFIG.http_password = strndup(password, MAX_FILENAME_LEN);
     SONIC_CONFIG.client = DEFAULT_USER_AGENT;
     /*
      * API 1.13.0 is the minimum version that supports
@@ -47,16 +49,16 @@ void sonic_config_init(const char *server, const char *username,
 static char *sonic_gen_auth_str()
 {
     char *salt = generate_salt();
-    size_t password_len = strnlen(SONIC_CONFIG.password, MAX_FILENAME_LEN);
+    size_t password_len = strnlen(SONIC_CONFIG.http_password, MAX_FILENAME_LEN);
     size_t password_salt_len = password_len + strnlen(salt, MAX_FILENAME_LEN);
     char *password_salt = CALLOC(password_salt_len + 1, sizeof(char));
-    strncat(password_salt, SONIC_CONFIG.password, MAX_FILENAME_LEN);
+    strncat(password_salt, SONIC_CONFIG.http_password, MAX_FILENAME_LEN);
     strncat(password_salt + password_len, salt, MAX_FILENAME_LEN);
     char *token = generate_md5sum(password_salt);
     char *auth_str = CALLOC(MAX_PATH_LEN + 1, sizeof(char));
     snprintf(auth_str, MAX_PATH_LEN,
                         ".view?u=%s&t=%s&s=%s&v=%s&c=%s",
-                        SONIC_CONFIG.username, token, salt,
+                        SONIC_CONFIG.http_username, token, salt,
                         SONIC_CONFIG.api_version, SONIC_CONFIG.client);
     free(salt);
     free(token);
@@ -76,27 +78,54 @@ static char *sonic_gen_url_first_part(char *method)
     return url;
 }
 
+/**
+ * \brief generate a getMusicDirectory request URL
+ */
+static char *sonic_getMusicDirectory_link(const int id)
+{
+    char *first_part = sonic_gen_url_first_part("getMusicDirectory");
+    char *url = CALLOC(MAX_PATH_LEN + 1, sizeof(char));
+    snprintf(url, MAX_PATH_LEN, "%s&id=%d", first_part, id);
+    free(first_part);
+    return url;
+}
+
+/**
+ * \brief generate a download request URL
+ */
+static char *sonic_download_link(const int id)
+{
+    char *first_part = sonic_gen_url_first_part("download");
+    char *url = CALLOC(MAX_PATH_LEN + 1, sizeof(char));
+    snprintf(url, MAX_PATH_LEN, "%s&id=%d", first_part, id);
+    free(first_part);
+    return url;
+}
+
 /**
  * \brief Process a single element output by the parser
  * \details This is the callback function called by the the XML parser.
  * \param[in] data user supplied data, in this case it is the pointer to the
  * LinkTable.
- * \param[in] element the name of this element, it should be either "child" or
+ * \param[in] elem the name of this element, it should be either "child" or
  * "artist"
- * \param[in] attributes Each attribute seen in a start (or empty) tag occupies
+ * \param[in] attr Each attribute seen in a start (or empty) tag occupies
  * 2 consecutive places in this vector: the attribute name followed by the
  * attribute value. These pairs are terminated by a null pointer.
+ * \note we are using strcmp rather than strncmp, because we are assuming the
+ * parser terminates the strings properly, which is a fair assumption,
+ * considering how mature expat is.
  */
-static void XMLCALL XML_process_single_element(void *data, const char *element,
+static void XMLCALL XML_process_single_element(void *data, const char *elem,
-                                               const char **attributes)
+                                               const char **attr)
 {
     LinkTable *linktbl = (LinkTable *) data;
     Link *link;
-    if (!strncmp(element, "child", 5)) {
+    if (!strcmp(elem, "child")) {
         /* Return from getMusicDirectory */
         link = CALLOC(1, sizeof(Link));
         link->type = LINK_INVALID;
-    } else if (!strncmp(element, "artist", 6)){
+    } else if (!strcmp(elem, "artist")){
         /* Return from getIndexes */
         link = CALLOC(1, sizeof(Link));
         link->type = LINK_DIR;
@@ -105,9 +134,78 @@ static void XMLCALL XML_process_single_element(void *data, const char *element,
         return;
     }
 
-    for (int i = 0; attributes[i]; i += 2) {
+    int id_set = 0;
+    int linkname_set = 0;
 
+    for (int i = 0; attr[i]; i += 2) {
+        if (!strcmp("id", attr[i])) {
+            link->sonic_id = atoi(attr[i+1]);
+            id_set = 1;
+            continue;
+        }
+
+        if (!strcmp("name", attr[i]) || !strcmp("title", attr[i])) {
+            strncpy(link->linkname, attr[i+1], MAX_FILENAME_LEN);
+            linkname_set = 1;
+            continue;
+        }
+
+        if (!strcmp("isDir", attr[i])) {
+            if (!strcmp("true", attr[i+1])) {
+                link->type = LINK_DIR;
+            } else if (!strcmp("false", attr[i+1])) {
+                link->type = LINK_FILE;
+            } else {
+                link->type = LINK_DIR;
+            }
+            continue;
+        }
+
+        if (!strcmp("created", attr[i])) {
+            struct tm *tm = calloc(1, sizeof(struct tm));
+            strptime(attr[i+1], "%Y-%m-%dT%H:%M:%S.000Z", tm);
+            link->time = mktime(tm);
+            free(tm);
+            continue;
+        }
+
+        if (!strcmp("size", attr[i])) {
+            link->content_length = atoll(attr[i+1]);
+            continue;
+        }
     }
+
+    /* Clean up if linkname is not set */
+    if (!linkname_set) {
+        free(link);
+        return;
+    }
+
+    /* Clean up if id is not set */
+    if (!id_set) {
+        if (linkname_set) {
+            free(link->linkname);
+        }
+        free(link);
+        return;
+    }
+
+    if (link->type == LINK_DIR) {
+        char *url = sonic_getMusicDirectory_link(link->sonic_id);
+        strncpy(link->f_url, url, MAX_PATH_LEN);
+        free(url);
+    } else if (link->type == LINK_FILE) {
+        char *url = sonic_download_link(link->sonic_id);
+        strncpy(link->f_url, url, MAX_PATH_LEN);
+        free(url);
+    } else {
+        /* Invalid link */
+        free(link->linkname);
+        free(link);
+        return;
+    }
+
+    LinkTable_add(linktbl, link);
 }
 
 /**
@@ -127,14 +225,12 @@ static void sonic_XML_to_LinkTable(DataStruct ds, LinkTable *linktbl)
     XML_ParserFree(parser);
 }
 
+
 LinkTable *sonic_LinkTable_new(const int id)
 {
     char *url;
     if (id > 0) {
-        char *first_part = sonic_gen_url_first_part("getMusicDirectory");
+        url = sonic_getMusicDirectory_link(id);
-        url = CALLOC(MAX_PATH_LEN + 1, sizeof(char));
-        snprintf(url, MAX_PATH_LEN, "%s&id=%d", first_part, id);
-        free(first_part);
     } else {
         url = sonic_gen_url_first_part("getIndexes");
     }
@@ -166,7 +262,7 @@ int main(int argc, char **argv)
 
     sonic_config_init(argv[1], argv[2], argv[3]);
 
-    NetworkConfig_init();
+    Config_init();
     NetworkSystem_init();
 
     sonic_LinkTable_new(0);

src/util.c

@@ -9,10 +9,86 @@
 #include <string.h>
 #include <errno.h>
 
+/**
+ * \brief Backtrace buffer size
+ */
 #define BT_BUF_SIZE 100
+
+/**
+ * \brief The length of a MD5SUM string
+ */
 #define MD5_HASH_LEN 32
+
+/**
+ * \brief The length of the salt
+ * \details This is basically the length of a UUID
+ */
 #define SALT_LEN 36
 
+/**
+ * \brief The default maximum number of network connections
+ */
+#define DEFAULT_NETWORK_MAX_CONNS   10
+
+/**
+ * \brief The default HTTP 429 (too many requests) wait time
+ */
+#define DEFAULT_HTTP_WAIT_SEC       5
+/**
+ * \brief Data file block size
+ * \details We set it to 1024*1024*8 = 8MiB
+ */
+#define DEFAULT_DATA_BLKSZ         8*1024*1024
+
+/**
+ * \brief Maximum segment block count
+ * \details This is set to 128*1024 blocks, which uses 128KB. By default,
+ * this allows the user to store (128*1024)*(8*1024*1024) = 1TB of data
+ */
+#define DEFAULT_MAX_SEGBC           128*1024
+
+ConfigStruct CONFIG;
+
+/**
+ * \note The opening curly bracket should be at line 39, so the code lines up
+ * with the definition code in util.h.
+ */
+void Config_init(void)
+{
+    /*---------------- Network related --------------*/
+    CONFIG.http_username = NULL;
+
+    CONFIG.http_password = NULL;
+
+    CONFIG.proxy = NULL;
+
+    CONFIG.proxy_username = NULL;
+
+    CONFIG.proxy_password = NULL;
+
+    CONFIG.max_conns = DEFAULT_NETWORK_MAX_CONNS;
+
+    CONFIG.user_agent = DEFAULT_USER_AGENT;
+
+    CONFIG.http_wait_sec = DEFAULT_HTTP_WAIT_SEC;
+
+    /*--------------- Cache related ---------------*/
+    CONFIG.cache_enabled = 0;
+
+    CONFIG.cache_dir = NULL;
+
+    CONFIG.data_blksz = DEFAULT_DATA_BLKSZ;
+
+    CONFIG.max_segbc = DEFAULT_MAX_SEGBC;
+
+    /*-------------- Subsonic related -------------*/
+    CONFIG.sonic_mode = 0;
+
+    CONFIG.sonic_username = NULL;
+
+    CONFIG.sonic_password = NULL;
+}
+
 char *path_append(const char *path, const char *filename)
 {
     int needs_separator = 0;
@@ -123,3 +199,4 @@ void *CALLOC(size_t nmemb, size_t size)
     }
     return ptr;
 }
+

src/util.h

@@ -21,6 +21,61 @@
  */
 #define MAX_FILENAME_LEN    255
 
+/**
+ * \brief the default user agent string
+ */
+#define DEFAULT_USER_AGENT "HTTPDirFS-" VERSION
+
+
+
+
+
+
+/**
+ * \brief configuration data structure
+ * \note The opening curly bracket should be at line 39, so the code belong
+ * lines up with the initialisation code in util.c
+ */
+typedef struct {
+    /** \brief HTTP username */
+    char *http_username;
+    /** \brief HTTP password */
+    char *http_password;
+    /** \brief HTTP proxy URL */
+    char *proxy;
+    /** \brief HTTP proxy username */
+    char *proxy_username;
+    /** \brief HTTP proxy password */
+    char *proxy_password;
+    /** \brief HTTP maximum connection count */
+    long max_conns;
+    /** \brief HTTP user agent*/
+    char *user_agent;
+    /** \brief The waiting time after getting HTTP 429 (too many requests) */
+    int http_wait_sec;
+
+    /** \brief Whether cache mode is enabled */
+    int cache_enabled;
+    /** \brief The cache location*/
+    char *cache_dir;
+    /** \brief The size of each download segment for cache mode */
+    int data_blksz;
+    /** \brief The maximum segment count for a single cache file */
+    int max_segbc;
+
+    /** \brief Whether we are using the Subsonic mode */
+    int sonic_mode;
+    /** \brief The Subsonic server username */
+    char *sonic_username;
+    /** \brief The Subsonic server password */
+    char *sonic_password;
+} ConfigStruct;
+
+/**
+ * \brief The Configuration data structure
+ */
+extern ConfigStruct CONFIG;
+
 /**
  * \brief append a path
  * \details This function appends a path with the next level, while taking the
@@ -74,4 +129,9 @@ char *generate_md5sum(const char *str);
  */
 void *CALLOC(size_t nmemb, size_t size);
 
+/**
+ * \brief initialise the configuration data structure
+ */
+void Config_init(void);
+
 #endif