// ============================================================================ //forum example to demonstrate G-WAN's API //http://forum.gwan.com/index.php?p=/discussion/470/forum-software-written-in-c/ // // Created by Eric Schulz (Ers35) //------------------------------------------------------------------------------ //include required headers------------------------------------------------------ #include "gwan.h" #include #include //------------------------------------------------------------------------------ //data structures--------------------------------------------------------------- typedef struct { u64 id; xbuf_t body; } Post; typedef struct { u64 id; xbuf_t title; kv_t posts; } Thread; //------------------------------------------------------------------------------ //HTML templates---------------------------------------------------------------- static char base_tpl[] = "" "G-WAN Forum" "

G-WAN Forum

" "" "" "", post_form[] = "

" //title of thread "" //thread id "" //new post "
" "", thread_form[] = "" //new thread "" ""; //------------------------------------------------------------------------------ //template rendering functions-------------------------------------------------- int list_posts(kv_item *item, xbuf_t *reply) { Post *post = (Post*)item->val; //using HTML comments const char post_li[] = "

"; char *pos = (char*)xbuf_findstr(reply, ""); if (pos) xbuf_insert(reply, pos, sizeof(post_li), (char*)post_li); xbuf_repl(reply, "", post->body.ptr); return 1; //continue searching } int list_threads(kv_item *item, xbuf_t *reply) { Thread *thread = (Thread*)item->val; xbuf_t thread_li; xbuf_init(&thread_li); //using sprintf-like formatting xbuf_xcat(&thread_li, "

" "%s (%lu)" "

", thread->id, thread->title.ptr, thread->posts.nbr_items ); char *pos = (char*)xbuf_findstr(reply, ""); if (pos) xbuf_insert(reply, pos, thread_li.len, thread_li.ptr); xbuf_free(&thread_li); return 1; } //------------------------------------------------------------------------------ int main(int argc, char *argv[]) { //initialize Key-Value store-------------------------------------------------- kv_t **vhost_ptr = (kv_t**)get_env(argv, US_VHOST_DATA), //persistent ptr *forum_store = 0; //convenience pointer (var->m instead of (*var)->m) if (vhost_ptr && !*vhost_ptr) { *vhost_ptr = (kv_t*)malloc(sizeof(kv_t)); //threads and posts stored here kv_init(*vhost_ptr, "forum_store", 1024, 0, 0, 0); } forum_store = *vhost_ptr; //---------------------------------------------------------------------------- //setup GET and POST variables------------------------------------------------ char *act = "", *id = "", *title = "", *body = ""; get_arg("act=", &act, argc, argv); //action ('t' or 'p') get_arg("id=", &id, argc, argv); //id of thread get_arg("title=", &title, argc, argv); //title of thread get_arg("body=", &body, argc, argv); //body of post char *end = 0; u64 int_id = strtoll(id, &end, 10); //string to integer if (*end) int_id = 0; //require a numeric ID //---------------------------------------------------------------------------- //response sent to browser is stored here------------------------------------- //templates are rendered into this buffer xbuf_t *reply = get_reply(argv); xbuf_cat(reply, base_tpl); //set base template //---------------------------------------------------------------------------- //HTTP state of a connection http_t *http = (http_t*)get_env(argv, HTTP_HEADERS); redirect: //simulate HTTP, , or JavaScript redirect without page reload //choose what to do based on the value of 'act'------------------------------- switch (*act) { //regarding a post case 'p': { switch (http->h_method) //GET or POST { //new post-------------------------------------------------------------- case HTTP_POST: { //get the thread to which this post belongs Thread *thread = (Thread*)kv_get(forum_store, (char*)&int_id, sizeof(int_id)); if (!thread) //thread not found { xbuf_repl(reply, "", http_error(404)); return HTTP_404_NOT_FOUND; } //allocate memory Post *post = calloc(1, sizeof(*post)); //initialize members xbuf_init(&post->body); //define members post->id = thread->posts.nbr_items + 1; xbuf_cat(&post->body, *body ? body : " "); //add post to thread kv_add(&thread->posts, &(kv_item) { .key = (char*)&post->id, .klen = sizeof(post->id), .val = (char*)post, .in_use = 0, }); //setup redirect http->h_method = HTTP_GET; *act = 't'; goto redirect; } break; //---------------------------------------------------------------------- } } break; //regarding a thread case 't': { switch (http->h_method) { //view a thread--------------------------------------------------------- case HTTP_GET: { Thread *thread = (Thread*)kv_get(forum_store, (char*)&int_id, sizeof(int_id)); if (!thread) { xbuf_repl(reply, "", http_error(404)); return HTTP_404_NOT_FOUND; } //replace template variables with dynamic values xbuf_repl(reply, "", post_form); xbuf_repl(reply, "", thread->title.ptr); xbuf_repl(reply, "", id); //for each post, render its template and insert it into reply kv_do(&thread->posts, 0, 0, (kv_proc_t)&list_posts, (void*)reply); } break; //---------------------------------------------------------------------- //create a thread------------------------------------------------------- case HTTP_POST: { Thread *thread = calloc(1, sizeof(*thread)); xbuf_init(&thread->title); kv_init(&thread->posts, "posts", 1024, 0, 0, 0); thread->id = forum_store->nbr_items + 1; xbuf_cat(&thread->title, *title ? title : " "); //add thread to KV store kv_add(forum_store, &(kv_item) { .key = (char*)&thread->id, .klen = sizeof(thread->id), .val = (char*)thread, .in_use = 0, }); http->h_method = HTTP_GET; *act = 0; goto redirect; } break; //---------------------------------------------------------------------- } } break; //list all threads---------------------------------------------------------- default: { xbuf_repl(reply, "", thread_form); kv_do(forum_store, 0, 0, (kv_proc_t)&list_threads, reply); } break; //-------------------------------------------------------------------------- } //---------------------------------------------------------------------------- return HTTP_200_OK; //HTTP code 200, no errors, headers generated automatically }