1 files changed, 166 insertions, 0 deletions
diff --git a/docs/code/uvwget/main.c b/docs/code/uvwget/main.c
new file mode 100644
index 00000000..40186241
--- /dev/null
+++ b/docs/code/uvwget/main.c
@@ -0,0 +1,166 @@
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <uv.h>
+#include <curl/curl.h>
+
+uv_loop_t *loop;
+CURLM *curl_handle;
+uv_timer_t timeout;
+
+typedef struct curl_context_s {
+    uv_poll_t poll_handle;
+    curl_socket_t sockfd;
+} curl_context_t;
+
+curl_context_t *create_curl_context(curl_socket_t sockfd) {
+    curl_context_t *context;
+
+    context = (curl_context_t*) malloc(sizeof *context);
+
+    context->sockfd = sockfd;
+
+    int r = uv_poll_init_socket(loop, &context->poll_handle, sockfd);
+    assert(r == 0);
+    context->poll_handle.data = context;
+
+    return context;
+}
+
+void curl_close_cb(uv_handle_t *handle) {
+    curl_context_t *context = (curl_context_t*) handle->data;
+    free(context);
+}
+
+void destroy_curl_context(curl_context_t *context) {
+    uv_close((uv_handle_t*) &context->poll_handle, curl_close_cb);
+}
+
+
+void add_download(const char *url, int num) {
+    char filename[50];
+    sprintf(filename, "%d.download", num);
+    FILE *file;
+
+    file = fopen(filename, "w");
+    if (file == NULL) {
+        fprintf(stderr, "Error opening %s\n", filename);
+        return;
+    }
+
+    CURL *handle = curl_easy_init();
+    curl_easy_setopt(handle, CURLOPT_WRITEDATA, file);
+    curl_easy_setopt(handle, CURLOPT_URL, url);
+    curl_multi_add_handle(curl_handle, handle);
+    fprintf(stderr, "Added download %s -> %s\n", url, filename);
+}
+
+void check_multi_info(void) {
+    char *done_url;
+    CURLMsg *message;
+    int pending;
+
+    while ((message = curl_multi_info_read(curl_handle, &pending))) {
+        switch (message->msg) {
+        case CURLMSG_DONE:
+            curl_easy_getinfo(message->easy_handle, CURLINFO_EFFECTIVE_URL,
+                            &done_url);
+            printf("%s DONE\n", done_url);
+
+            curl_multi_remove_handle(curl_handle, message->easy_handle);
+            curl_easy_cleanup(message->easy_handle);
+            break;
+
+        default:
+            fprintf(stderr, "CURLMSG default\n");
+            abort();
+        }
+    }
+}
+
+void curl_perform(uv_poll_t *req, int status, int events) {
+    uv_timer_stop(&timeout);
+    int running_handles;
+    int flags = 0;
+    if (status < 0)                      flags = CURL_CSELECT_ERR;
+    if (!status && events & UV_READABLE) flags |= CURL_CSELECT_IN;
+    if (!status && events & UV_WRITABLE) flags |= CURL_CSELECT_OUT;
+
+    curl_context_t *context;
+
+    context = (curl_context_t*)req;
+
+    curl_multi_socket_action(curl_handle, context->sockfd, flags, &running_handles);
+    check_multi_info();   
+}
+
+void on_timeout(uv_timer_t *req) {
+    int running_handles;
+    curl_multi_socket_action(curl_handle, CURL_SOCKET_TIMEOUT, 0, &running_handles);
+    check_multi_info();
+}
+
+void start_timeout(CURLM *multi, long timeout_ms, void *userp) {
+    if (timeout_ms <= 0)
+        timeout_ms = 1; /* 0 means directly call socket_action, but we'll do it in a bit */
+    uv_timer_start(&timeout, on_timeout, timeout_ms, 0);
+}
+
+int handle_socket(CURL *easy, curl_socket_t s, int action, void *userp, void *socketp) {
+    curl_context_t *curl_context;
+    if (action == CURL_POLL_IN || action == CURL_POLL_OUT) {
+        if (socketp) {
+            curl_context = (curl_context_t*) socketp;
+        }
+        else {
+            curl_context = create_curl_context(s);
+            curl_multi_assign(curl_handle, s, (void *) curl_context);
+        }
+    }
+
+    switch (action) {
+        case CURL_POLL_IN:
+            uv_poll_start(&curl_context->poll_handle, UV_READABLE, curl_perform);
+            break;
+        case CURL_POLL_OUT:
+            uv_poll_start(&curl_context->poll_handle, UV_WRITABLE, curl_perform);
+            break;
+        case CURL_POLL_REMOVE:
+            if (socketp) {
+                uv_poll_stop(&((curl_context_t*)socketp)->poll_handle);
+                destroy_curl_context((curl_context_t*) socketp);                
+                curl_multi_assign(curl_handle, s, NULL);
+            }
+            break;
+        default:
+            abort();
+    }
+
+    return 0;
+}
+
+int main(int argc, char **argv) {
+    loop = uv_default_loop();
+
+    if (argc <= 1)
+        return 0;
+
+    if (curl_global_init(CURL_GLOBAL_ALL)) {
+        fprintf(stderr, "Could not init cURL\n");
+        return 1;
+    }
+
+    uv_timer_init(loop, &timeout);
+
+    curl_handle = curl_multi_init();
+    curl_multi_setopt(curl_handle, CURLMOPT_SOCKETFUNCTION, handle_socket);
+    curl_multi_setopt(curl_handle, CURLMOPT_TIMERFUNCTION, start_timeout);
+
+    while (argc-- > 1) {
+        add_download(argv[argc], argc);
+    }
+
+    uv_run(loop, UV_RUN_DEFAULT);
+    curl_multi_cleanup(curl_handle);
+    return 0;
+}