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-rw-r--r--docs/examples/Makefile.inc2
-rw-r--r--docs/examples/ephiperfifo.c540
2 files changed, 541 insertions, 1 deletions
diff --git a/docs/examples/Makefile.inc b/docs/examples/Makefile.inc
index 9215b82fb..72eb0d4b8 100644
--- a/docs/examples/Makefile.inc
+++ b/docs/examples/Makefile.inc
@@ -43,4 +43,4 @@ COMPLICATED_EXAMPLES = curlgtk.c curlx.c htmltitle.cpp cacertinmem.c \
sampleconv.c synctime.c threaded-ssl.c evhiperfifo.c \
smooth-gtk-thread.c version-check.pl href_extractor.c asiohiper.cpp \
multi-uv.c xmlstream.c usercertinmem.c sessioninfo.c \
- threaded-shared-conn.c crawler.c
+ threaded-shared-conn.c crawler.c ephiperfifo.c
diff --git a/docs/examples/ephiperfifo.c b/docs/examples/ephiperfifo.c
new file mode 100644
index 000000000..e11715f1c
--- /dev/null
+++ b/docs/examples/ephiperfifo.c
@@ -0,0 +1,540 @@
+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+/* <DESC>
+ * multi socket API usage with epoll and timerfd
+ * </DESC>
+ */
+/* Example application source code using the multi socket interface to
+ * download many files at once.
+ *
+ * This example features the same basic functionality as hiperfifo.c does,
+ * but this uses epoll and timerfd instead of libevent.
+ *
+ * Written by Jeff Pohlmeyer, converted to use epoll by Josh Bialkowski
+
+Requires a linux system with epoll
+
+When running, the program creates the named pipe "hiper.fifo"
+
+Whenever there is input into the fifo, the program reads the input as a list
+of URL's and creates some new easy handles to fetch each URL via the
+curl_multi "hiper" API.
+
+
+Thus, you can try a single URL:
+ % echo http://www.yahoo.com > hiper.fifo
+
+Or a whole bunch of them:
+ % cat my-url-list > hiper.fifo
+
+The fifo buffer is handled almost instantly, so you can even add more URL's
+while the previous requests are still being downloaded.
+
+Note:
+ For the sake of simplicity, URL length is limited to 1023 char's !
+
+This is purely a demo app, all retrieved data is simply discarded by the write
+callback.
+
+*/
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/epoll.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/timerfd.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <curl/curl.h>
+#include <curl/multi.h>
+
+#ifdef __GNUC__
+#define _Unused __attribute__((unused))
+#else
+#define _Unused
+#endif
+
+#define MSG_OUT stdout /* Send info to stdout, change to stderr if you want */
+
+
+/* Global information, common to all connections */
+typedef struct _GlobalInfo
+{
+ int epfd; /* epoll filedescriptor */
+ int tfd; /* timer filedescriptor */
+ int fifofd; /* fifo filedescriptor */
+ CURLM *multi;
+ int still_running;
+ FILE *input;
+} GlobalInfo;
+
+
+/* Information associated with a specific easy handle */
+typedef struct _ConnInfo
+{
+ CURL *easy;
+ char *url;
+ GlobalInfo *global;
+ char error[CURL_ERROR_SIZE];
+} ConnInfo;
+
+
+/* Information associated with a specific socket */
+typedef struct _SockInfo
+{
+ curl_socket_t sockfd;
+ CURL *easy;
+ int action;
+ long timeout;
+ GlobalInfo *global;
+} SockInfo;
+
+#define __case(code) \
+ case code: s = __STRING(code)
+
+/* Die if we get a bad CURLMcode somewhere */
+static void mcode_or_die(const char *where, CURLMcode code)
+{
+ if(CURLM_OK != code) {
+ const char *s;
+ switch(code) {
+ __case(CURLM_BAD_HANDLE); break;
+ __case(CURLM_BAD_EASY_HANDLE); break;
+ __case(CURLM_OUT_OF_MEMORY); break;
+ __case(CURLM_INTERNAL_ERROR); break;
+ __case(CURLM_UNKNOWN_OPTION); break;
+ __case(CURLM_LAST); break;
+ default: s = "CURLM_unknown"; break;
+ __case(CURLM_BAD_SOCKET);
+ fprintf(MSG_OUT, "ERROR: %s returns %s\n", where, s);
+ /* ignore this error */
+ return;
+ }
+ fprintf(MSG_OUT, "ERROR: %s returns %s\n", where, s);
+ exit(code);
+ }
+}
+
+static void timer_cb(GlobalInfo* g, int revents);
+
+/* Update the timer after curl_multi library does it's thing. Curl will
+ * inform us through this callback what it wants the new timeout to be,
+ * after it does some work. */
+static int multi_timer_cb(CURLM *multi, long timeout_ms, GlobalInfo *g)
+{
+ struct itimerspec its;
+ CURLMcode rc;
+
+ fprintf(MSG_OUT, "multi_timer_cb: Setting timeout to %ld ms\n", timeout_ms);
+
+ timerfd_settime(g->tfd, /*flags=*/0, &its, NULL);
+ if (timeout_ms > 0) {
+ its.it_interval.tv_sec = 1;
+ its.it_interval.tv_nsec = 0;
+ its.it_value.tv_sec = timeout_ms / 1000;
+ its.it_value.tv_nsec = (timeout_ms % 1000) * 1000;
+ timerfd_settime(g->tfd, /*flags=*/0, &its, NULL);
+ } else if (timeout_ms == 0) {
+ rc = curl_multi_socket_action(g->multi,
+ CURL_SOCKET_TIMEOUT, 0, &g->still_running);
+ mcode_or_die("multi_timer_cb: curl_multi_socket_action", rc);
+ } else {
+ memset(&its, 0, sizeof(struct itimerspec));
+ timerfd_settime(g->tfd, /*flags=*/0, &its, NULL);
+ }
+ return 0;
+}
+
+
+/* Check for completed transfers, and remove their easy handles */
+static void check_multi_info(GlobalInfo *g)
+{
+ char *eff_url;
+ CURLMsg *msg;
+ int msgs_left;
+ ConnInfo *conn;
+ CURL *easy;
+ CURLcode res;
+
+ fprintf(MSG_OUT, "REMAINING: %d\n", g->still_running);
+ while((msg = curl_multi_info_read(g->multi, &msgs_left))) {
+ if(msg->msg == CURLMSG_DONE) {
+ easy = msg->easy_handle;
+ res = msg->data.result;
+ curl_easy_getinfo(easy, CURLINFO_PRIVATE, &conn);
+ curl_easy_getinfo(easy, CURLINFO_EFFECTIVE_URL, &eff_url);
+ fprintf(MSG_OUT, "DONE: %s => (%d) %s\n", eff_url, res, conn->error);
+ curl_multi_remove_handle(g->multi, easy);
+ free(conn->url);
+ curl_easy_cleanup(easy);
+ free(conn);
+ }
+ }
+}
+
+/* Called by libevent when we get action on a multi socket filedescriptor*/
+static void event_cb(GlobalInfo *g, int fd, int revents)
+{
+ CURLMcode rc;
+ struct itimerspec its;
+
+ int action = (revents & EPOLLIN ? CURL_POLL_IN : 0) |
+ (revents & EPOLLOUT ? CURL_POLL_OUT : 0);
+
+ rc = curl_multi_socket_action(g->multi, fd, action, &g->still_running);
+ mcode_or_die("event_cb: curl_multi_socket_action", rc);
+
+ check_multi_info(g);
+ if(g->still_running <= 0) {
+ fprintf(MSG_OUT, "last transfer done, kill timeout\n");
+ memset(&its, 0, sizeof(struct itimerspec));
+ timerfd_settime(g->tfd, 0, &its, NULL);
+ }
+}
+
+/* Called by main loop when our timeout expires */
+static void timer_cb(GlobalInfo* g, int revents)
+{
+ CURLMcode rc;
+ uint64_t count = 0;
+ ssize_t err = 0;
+
+ err = read(g->tfd, &count, sizeof(uint64_t));
+ if(err == -1) {
+ /* Note that we may call the timer callback even if the timerfd isn't
+ * readable. It's possible that there are multiple events stored in the
+ * epoll buffer (i.e. the timer may have fired multiple times). The
+ * event count is cleared after the first call so future events in the
+ * epoll buffer will fail to read from the timer. */
+ if (errno == EAGAIN) {
+ fprintf(MSG_OUT, "EAGAIN on tfd %d\n", g->tfd);
+ return;
+ }
+ }
+ if(err != sizeof(uint64_t)){
+ fprintf(stderr, "read(tfd) == %ld", err);
+ perror("read(tfd)");
+ }
+
+ rc = curl_multi_socket_action(g->multi,
+ CURL_SOCKET_TIMEOUT, 0, &g->still_running);
+ mcode_or_die("timer_cb: curl_multi_socket_action", rc);
+ check_multi_info(g);
+}
+
+
+
+/* Clean up the SockInfo structure */
+static void remsock(SockInfo *f, GlobalInfo* g)
+{
+ if(f) {
+ if(f->sockfd) {
+ epoll_ctl(g->epfd, EPOLL_CTL_DEL, f->sockfd, NULL);
+ }
+ free(f);
+ }
+}
+
+
+
+/* Assign information to a SockInfo structure */
+static void setsock(SockInfo *f, curl_socket_t s, CURL *e, int act,
+ GlobalInfo *g)
+{
+ struct epoll_event ev;
+ int kind =
+ (act & CURL_POLL_IN ? EPOLLIN : 0) | (act & CURL_POLL_OUT ? EPOLLOUT : 0);
+
+ if(f->sockfd){
+ epoll_ctl(g->epfd, EPOLL_CTL_DEL, f->sockfd, NULL);
+ }
+
+ f->sockfd = s;
+ f->action = act;
+ f->easy = e;
+
+ ev.events = kind;
+ ev.data.fd = s;
+ epoll_ctl(g->epfd, EPOLL_CTL_ADD, s, &ev);
+}
+
+
+
+/* Initialize a new SockInfo structure */
+static void addsock(curl_socket_t s, CURL *easy, int action, GlobalInfo *g)
+{
+ SockInfo *fdp = (SockInfo*)calloc(sizeof(SockInfo), 1);
+
+ fdp->global = g;
+ setsock(fdp, s, easy, action, g);
+ curl_multi_assign(g->multi, s, fdp);
+}
+
+/* CURLMOPT_SOCKETFUNCTION */
+static int sock_cb(CURL *e, curl_socket_t s, int what, void *cbp, void *sockp)
+{
+ GlobalInfo *g = (GlobalInfo*) cbp;
+ SockInfo *fdp = (SockInfo*) sockp;
+ const char *whatstr[]={ "none", "IN", "OUT", "INOUT", "REMOVE" };
+
+ fprintf(MSG_OUT,
+ "socket callback: s=%d e=%p what=%s ", s, e, whatstr[what]);
+ if(what == CURL_POLL_REMOVE) {
+ fprintf(MSG_OUT, "\n");
+ remsock(fdp, g);
+ }
+ else {
+ if(!fdp) {
+ fprintf(MSG_OUT, "Adding data: %s\n", whatstr[what]);
+ addsock(s, e, what, g);
+ }
+ else {
+ fprintf(MSG_OUT,
+ "Changing action from %s to %s\n",
+ whatstr[fdp->action], whatstr[what]);
+ setsock(fdp, s, e, what, g);
+ }
+ }
+ return 0;
+}
+
+
+
+/* CURLOPT_WRITEFUNCTION */
+static size_t write_cb(void *ptr _Unused, size_t size, size_t nmemb,
+ void *data)
+{
+ size_t realsize = size * nmemb;
+ ConnInfo *conn _Unused = (ConnInfo*) data;
+
+ return realsize;
+}
+
+
+/* CURLOPT_PROGRESSFUNCTION */
+static int prog_cb(void *p, double dltotal, double dlnow, double ult _Unused,
+ double uln _Unused)
+{
+ ConnInfo *conn = (ConnInfo *)p;
+
+ fprintf(MSG_OUT, "Progress: %s (%g/%g)\n", conn->url, dlnow, dltotal);
+ return 0;
+}
+
+
+/* Create a new easy handle, and add it to the global curl_multi */
+static void new_conn(char *url, GlobalInfo *g)
+{
+ ConnInfo *conn;
+ CURLMcode rc;
+
+ conn = (ConnInfo*)calloc(1, sizeof(ConnInfo));
+ conn->error[0]='\0';
+
+ conn->easy = curl_easy_init();
+ if(!conn->easy) {
+ fprintf(MSG_OUT, "curl_easy_init() failed, exiting!\n");
+ exit(2);
+ }
+ conn->global = g;
+ conn->url = strdup(url);
+ curl_easy_setopt(conn->easy, CURLOPT_URL, conn->url);
+ curl_easy_setopt(conn->easy, CURLOPT_WRITEFUNCTION, write_cb);
+ curl_easy_setopt(conn->easy, CURLOPT_WRITEDATA, conn);
+ curl_easy_setopt(conn->easy, CURLOPT_VERBOSE, 1L);
+ curl_easy_setopt(conn->easy, CURLOPT_ERRORBUFFER, conn->error);
+ curl_easy_setopt(conn->easy, CURLOPT_PRIVATE, conn);
+ curl_easy_setopt(conn->easy, CURLOPT_NOPROGRESS, 0L);
+ curl_easy_setopt(conn->easy, CURLOPT_PROGRESSFUNCTION, prog_cb);
+ curl_easy_setopt(conn->easy, CURLOPT_PROGRESSDATA, conn);
+ curl_easy_setopt(conn->easy, CURLOPT_FOLLOWLOCATION, 1L);
+ curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_TIME, 3L);
+ curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_LIMIT, 10L);
+ fprintf(MSG_OUT,
+ "Adding easy %p to multi %p (%s)\n", conn->easy, g->multi, url);
+ rc = curl_multi_add_handle(g->multi, conn->easy);
+ mcode_or_die("new_conn: curl_multi_add_handle", rc);
+
+ /* note that the add_handle() will set a time-out to trigger very soon so
+ that the necessary socket_action() call will be called by this app */
+}
+
+/* This gets called whenever data is received from the fifo */
+static void fifo_cb(GlobalInfo* g, int revents)
+{
+ char s[1024];
+ long int rv = 0;
+ int n = 0;
+
+ do {
+ s[0]='\0';
+ rv = fscanf(g->input, "%1023s%n", s, &n);
+ s[n]='\0';
+ if(n && s[0]) {
+ new_conn(s, g); /* if we read a URL, go get it! */
+ } else
+ break;
+ } while(rv != EOF);
+}
+
+/* Create a named pipe and tell libevent to monitor it */
+static const char *fifo = "hiper.fifo";
+static int init_fifo(GlobalInfo *g)
+{
+ struct stat st;
+ curl_socket_t sockfd;
+ struct epoll_event epev;
+
+ fprintf(MSG_OUT, "Creating named pipe \"%s\"\n", fifo);
+ if(lstat (fifo, &st) == 0) {
+ if((st.st_mode & S_IFMT) == S_IFREG) {
+ errno = EEXIST;
+ perror("lstat");
+ exit(1);
+ }
+ }
+ unlink(fifo);
+ if(mkfifo (fifo, 0600) == -1) {
+ perror("mkfifo");
+ exit(1);
+ }
+ sockfd = open(fifo, O_RDWR | O_NONBLOCK, 0);
+ if(sockfd == -1) {
+ perror("open");
+ exit(1);
+ }
+
+ g->fifofd = sockfd;
+ g->input = fdopen(sockfd, "r");
+
+ epev.events = EPOLLIN;
+ epev.data.fd = sockfd;
+ epoll_ctl(g->epfd, EPOLL_CTL_ADD, sockfd, &epev);
+
+ fprintf(MSG_OUT, "Now, pipe some URL's into > %s\n", fifo);
+ return 0;
+}
+
+static void clean_fifo(GlobalInfo *g)
+{
+ epoll_ctl(g->epfd, EPOLL_CTL_DEL, g->fifofd, NULL);
+ fclose(g->input);
+ unlink(fifo);
+}
+
+
+int g_should_exit_ = 0;
+
+void SignalHandler(int signo) {
+ if (signo == SIGINT) {
+ g_should_exit_ = 1;
+ }
+}
+
+int main(int argc _Unused, char **argv _Unused)
+{
+ GlobalInfo g;
+ int err;
+ int idx;
+ struct itimerspec its;
+ struct epoll_event ev;
+ struct epoll_event events[10];
+
+ g_should_exit_ = 0;
+ signal(SIGINT, SignalHandler);
+
+ memset(&g, 0, sizeof(GlobalInfo));
+ g.epfd = epoll_create1(EPOLL_CLOEXEC);
+ if(g.epfd == -1) {
+ perror("epoll_create1 failed");
+ exit(1);
+ }
+
+ g.tfd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
+ if(g.tfd == -1) {
+ perror("timerfd_create failed");
+ exit(1);
+ }
+
+ memset(&its, 0, sizeof(struct itimerspec));
+ its.it_interval.tv_sec = 1;
+ its.it_value.tv_sec = 1;
+ timerfd_settime(g.tfd, 0, &its, NULL);
+
+ ev.events = EPOLLIN;
+ ev.data.fd = g.tfd;
+ epoll_ctl(g.epfd, EPOLL_CTL_ADD, g.tfd, &ev);
+
+ init_fifo(&g);
+ g.multi = curl_multi_init();
+
+ /* setup the generic multi interface options we want */
+ curl_multi_setopt(g.multi, CURLMOPT_SOCKETFUNCTION, sock_cb);
+ curl_multi_setopt(g.multi, CURLMOPT_SOCKETDATA, &g);
+ curl_multi_setopt(g.multi, CURLMOPT_TIMERFUNCTION, multi_timer_cb);
+ curl_multi_setopt(g.multi, CURLMOPT_TIMERDATA, &g);
+
+ /* we don't call any curl_multi_socket*() function yet as we have no handles
+ added! */
+
+ fprintf(MSG_OUT, "Entering wait loop\n");
+ fflush(MSG_OUT);
+ while (!g_should_exit_) {
+ /* TODO(josh): use epoll_pwait to avoid a race on the signal. Mask the
+ * signal before the while loop, and then re-enable the signal during
+ * epoll wait. Mask at the end of the loop. */
+ err = epoll_wait(g.epfd, events, sizeof(events)/sizeof(struct epoll_event),
+ 10000);
+ if (err == -1) {
+ if (errno == EINTR) {
+ fprintf(MSG_OUT, "note: wait interrupted\n");
+ continue;
+ } else {
+ perror("epoll_wait");
+ exit(1);
+ }
+ }
+
+ for (idx = 0; idx < err; ++idx) {
+ if (events[idx].data.fd == g.fifofd) {
+ fifo_cb(&g, events[idx].events);
+ } else if (events[idx].data.fd == g.tfd) {
+ timer_cb(&g, events[idx].events);
+ } else {
+ event_cb(&g, events[idx].data.fd, events[idx].events);
+ }
+ }
+ }
+
+ fprintf(MSG_OUT, "Exiting normally.\n");
+ fflush(MSG_OUT);
+
+ curl_multi_cleanup(g.multi);
+ return 0;
+}
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