--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/curl/docs/examples/hiperfifo.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,458 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2019, 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 libevent 2
+ * </DESC>
+ */
+/* Example application source code using the multi socket interface to
+   download many files at once.
+
+Written by Jeff Pohlmeyer
+
+Requires libevent version 2 and a (POSIX?) system that has mkfifo().
+
+This is an adaptation of libcurl's "hipev.c" and libevent's "event-test.c"
+sample programs.
+
+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 <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/poll.h>
+#include <curl/curl.h>
+#include <event2/event.h>
+#include <event2/event_struct.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <sys/cdefs.h>
+
+#define MSG_OUT stdout /* Send info to stdout, change to stderr if you want */
+
+
+/* Global information, common to all connections */
+typedef struct _GlobalInfo
+{
+  struct event_base *evbase;
+  struct event fifo_event;
+  struct event timer_event;
+  CURLM *multi;
+  int still_running;
+  FILE *input;
+  int stopped;
+} 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;
+  struct event ev;
+  GlobalInfo *global;
+} SockInfo;
+
+#define mycase(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) {
+      mycase(CURLM_BAD_HANDLE); break;
+      mycase(CURLM_BAD_EASY_HANDLE); break;
+      mycase(CURLM_OUT_OF_MEMORY); break;
+      mycase(CURLM_INTERNAL_ERROR); break;
+      mycase(CURLM_UNKNOWN_OPTION); break;
+      mycase(CURLM_LAST); break;
+      default: s = "CURLM_unknown"; break;
+      mycase(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);
+  }
+}
+
+
+/* Update the event timer after curl_multi library calls */
+static int multi_timer_cb(CURLM *multi, long timeout_ms, GlobalInfo *g)
+{
+  struct timeval timeout;
+  (void)multi;
+
+  timeout.tv_sec = timeout_ms/1000;
+  timeout.tv_usec = (timeout_ms%1000)*1000;
+  fprintf(MSG_OUT, "multi_timer_cb: Setting timeout to %ld ms\n", timeout_ms);
+
+  /*
+   * if timeout_ms is -1, just delete the timer
+   *
+   * For all other values of timeout_ms, this should set or *update* the timer
+   * to the new value
+   */
+  if(timeout_ms == -1)
+    evtimer_del(&g->timer_event);
+  else /* includes timeout zero */
+    evtimer_add(&g->timer_event, &timeout);
+  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);
+    }
+  }
+  if(g->still_running == 0 && g->stopped)
+    event_base_loopbreak(g->evbase);
+}
+
+
+
+/* Called by libevent when we get action on a multi socket */
+static void event_cb(int fd, short kind, void *userp)
+{
+  GlobalInfo *g = (GlobalInfo*) userp;
+  CURLMcode rc;
+
+  int action =
+    ((kind & EV_READ) ? CURL_CSELECT_IN : 0) |
+    ((kind & EV_WRITE) ? CURL_CSELECT_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");
+    if(evtimer_pending(&g->timer_event, NULL)) {
+      evtimer_del(&g->timer_event);
+    }
+  }
+}
+
+
+
+/* Called by libevent when our timeout expires */
+static void timer_cb(int fd, short kind, void *userp)
+{
+  GlobalInfo *g = (GlobalInfo *)userp;
+  CURLMcode rc;
+  (void)fd;
+  (void)kind;
+
+  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)
+{
+  if(f) {
+    event_del(&f->ev);
+    free(f);
+  }
+}
+
+
+
+/* Assign information to a SockInfo structure */
+static void setsock(SockInfo *f, curl_socket_t s, CURL *e, int act,
+                    GlobalInfo *g)
+{
+  int kind =
+     ((act & CURL_POLL_IN) ? EV_READ : 0) |
+     ((act & CURL_POLL_OUT) ? EV_WRITE : 0) | EV_PERSIST;
+
+  f->sockfd = s;
+  f->action = act;
+  f->easy = e;
+  event_del(&f->ev);
+  event_assign(&f->ev, g->evbase, f->sockfd, kind, event_cb, g);
+  event_add(&f->ev, NULL);
+}
+
+
+
+/* Initialize a new SockInfo structure */
+static void addsock(curl_socket_t s, CURL *easy, int action, GlobalInfo *g)
+{
+  SockInfo *fdp = 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);
+  }
+  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, size_t size, size_t nmemb, void *data)
+{
+  (void)ptr;
+  (void)data;
+  return size * nmemb;
+}
+
+
+/* CURLOPT_PROGRESSFUNCTION */
+static int prog_cb(void *p, double dltotal, double dlnow, double ult,
+                   double uln)
+{
+  ConnInfo *conn = (ConnInfo *)p;
+  (void)ult;
+  (void)uln;
+
+  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 = 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);
+  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(int fd, short event, void *arg)
+{
+  char s[1024];
+  long int rv = 0;
+  int n = 0;
+  GlobalInfo *g = (GlobalInfo *)arg;
+  (void)fd;
+  (void)event;
+
+  do {
+    s[0]='\0';
+    rv = fscanf(g->input, "%1023s%n", s, &n);
+    s[n]='\0';
+    if(n && s[0]) {
+      if(!strcmp(s, "stop")) {
+        g->stopped = 1;
+        if(g->still_running == 0)
+          event_base_loopbreak(g->evbase);
+      }
+      else
+        new_conn(s, arg);  /* 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;
+
+  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->input = fdopen(sockfd, "r");
+
+  fprintf(MSG_OUT, "Now, pipe some URL's into > %s\n", fifo);
+  event_assign(&g->fifo_event, g->evbase, sockfd, EV_READ|EV_PERSIST,
+               fifo_cb, g);
+  event_add(&g->fifo_event, NULL);
+  return (0);
+}
+
+static void clean_fifo(GlobalInfo *g)
+{
+    event_del(&g->fifo_event);
+    fclose(g->input);
+    unlink(fifo);
+}
+
+int main(int argc, char **argv)
+{
+  GlobalInfo g;
+  (void)argc;
+  (void)argv;
+
+  memset(&g, 0, sizeof(GlobalInfo));
+  g.evbase = event_base_new();
+  init_fifo(&g);
+  g.multi = curl_multi_init();
+  evtimer_assign(&g.timer_event, g.evbase, timer_cb, &g);
+
+  /* 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! */
+
+  event_base_dispatch(g.evbase);
+
+  /* this, of course, won't get called since only way to stop this program is
+     via ctrl-C, but it is here to show how cleanup /would/ be done. */
+  clean_fifo(&g);
+  event_del(&g.timer_event);
+  event_base_free(g.evbase);
+  curl_multi_cleanup(g.multi);
+  return 0;
+}