--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/curl/docs/examples/multi-debugcallback.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,231 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  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 interface and debug callback
+ * </DESC>
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+/* somewhat unix-specific */
+#include <sys/time.h>
+#include <unistd.h>
+
+/* curl stuff */
+#include <curl/curl.h>
+
+typedef char bool;
+#define TRUE 1
+
+static
+void dump(const char *text,
+          FILE *stream, unsigned char *ptr, size_t size,
+          bool nohex)
+{
+  size_t i;
+  size_t c;
+
+  unsigned int width = 0x10;
+
+  if(nohex)
+    /* without the hex output, we can fit more on screen */
+    width = 0x40;
+
+  fprintf(stream, "%s, %10.10lu bytes (0x%8.8lx)\n",
+          text, (unsigned long)size, (unsigned long)size);
+
+  for(i = 0; i<size; i += width) {
+
+    fprintf(stream, "%4.4lx: ", (unsigned long)i);
+
+    if(!nohex) {
+      /* hex not disabled, show it */
+      for(c = 0; c < width; c++)
+        if(i + c < size)
+          fprintf(stream, "%02x ", ptr[i + c]);
+        else
+          fputs("   ", stream);
+    }
+
+    for(c = 0; (c < width) && (i + c < size); c++) {
+      /* check for 0D0A; if found, skip past and start a new line of output */
+      if(nohex && (i + c + 1 < size) && ptr[i + c] == 0x0D &&
+         ptr[i + c + 1] == 0x0A) {
+        i += (c + 2 - width);
+        break;
+      }
+      fprintf(stream, "%c",
+              (ptr[i + c] >= 0x20) && (ptr[i + c]<0x80)?ptr[i + c]:'.');
+      /* check again for 0D0A, to avoid an extra \n if it's at width */
+      if(nohex && (i + c + 2 < size) && ptr[i + c + 1] == 0x0D &&
+         ptr[i + c + 2] == 0x0A) {
+        i += (c + 3 - width);
+        break;
+      }
+    }
+    fputc('\n', stream); /* newline */
+  }
+  fflush(stream);
+}
+
+static
+int my_trace(CURL *handle, curl_infotype type,
+             unsigned char *data, size_t size,
+             void *userp)
+{
+  const char *text;
+
+  (void)userp;
+  (void)handle; /* prevent compiler warning */
+
+  switch(type) {
+  case CURLINFO_TEXT:
+    fprintf(stderr, "== Info: %s", data);
+    /* FALLTHROUGH */
+  default: /* in case a new one is introduced to shock us */
+    return 0;
+
+  case CURLINFO_HEADER_OUT:
+    text = "=> Send header";
+    break;
+  case CURLINFO_DATA_OUT:
+    text = "=> Send data";
+    break;
+  case CURLINFO_HEADER_IN:
+    text = "<= Recv header";
+    break;
+  case CURLINFO_DATA_IN:
+    text = "<= Recv data";
+    break;
+  }
+
+  dump(text, stderr, data, size, TRUE);
+  return 0;
+}
+
+/*
+ * Simply download a HTTP file.
+ */
+int main(void)
+{
+  CURL *http_handle;
+  CURLM *multi_handle;
+
+  int still_running = 0; /* keep number of running handles */
+
+  http_handle = curl_easy_init();
+
+  /* set the options (I left out a few, you'll get the point anyway) */
+  curl_easy_setopt(http_handle, CURLOPT_URL, "https://www.example.com/");
+
+  curl_easy_setopt(http_handle, CURLOPT_DEBUGFUNCTION, my_trace);
+  curl_easy_setopt(http_handle, CURLOPT_VERBOSE, 1L);
+
+  /* init a multi stack */
+  multi_handle = curl_multi_init();
+
+  /* add the individual transfers */
+  curl_multi_add_handle(multi_handle, http_handle);
+
+  /* we start some action by calling perform right away */
+  curl_multi_perform(multi_handle, &still_running);
+
+  while(still_running) {
+    struct timeval timeout;
+    int rc; /* select() return code */
+    CURLMcode mc; /* curl_multi_fdset() return code */
+
+    fd_set fdread;
+    fd_set fdwrite;
+    fd_set fdexcep;
+    int maxfd = -1;
+
+    long curl_timeo = -1;
+
+    FD_ZERO(&fdread);
+    FD_ZERO(&fdwrite);
+    FD_ZERO(&fdexcep);
+
+    /* set a suitable timeout to play around with */
+    timeout.tv_sec = 1;
+    timeout.tv_usec = 0;
+
+    curl_multi_timeout(multi_handle, &curl_timeo);
+    if(curl_timeo >= 0) {
+      timeout.tv_sec = curl_timeo / 1000;
+      if(timeout.tv_sec > 1)
+        timeout.tv_sec = 1;
+      else
+        timeout.tv_usec = (curl_timeo % 1000) * 1000;
+    }
+
+    /* get file descriptors from the transfers */
+    mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
+
+    if(mc != CURLM_OK) {
+      fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
+      break;
+    }
+
+    /* On success the value of maxfd is guaranteed to be >= -1. We call
+       select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
+       no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
+       to sleep 100ms, which is the minimum suggested value in the
+       curl_multi_fdset() doc. */
+
+    if(maxfd == -1) {
+#ifdef _WIN32
+      Sleep(100);
+      rc = 0;
+#else
+      /* Portable sleep for platforms other than Windows. */
+      struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
+      rc = select(0, NULL, NULL, NULL, &wait);
+#endif
+    }
+    else {
+      /* Note that on some platforms 'timeout' may be modified by select().
+         If you need access to the original value save a copy beforehand. */
+      rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);
+    }
+
+    switch(rc) {
+    case -1:
+      /* select error */
+      still_running = 0;
+      printf("select() returns error, this is badness\n");
+      break;
+    case 0:
+    default:
+      /* timeout or readable/writable sockets */
+      curl_multi_perform(multi_handle, &still_running);
+      break;
+    }
+  }
+
+  curl_multi_cleanup(multi_handle);
+
+  curl_easy_cleanup(http_handle);
+
+  return 0;
+}