--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/curl/docs/examples/post-callback.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,154 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2017, 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>
+ * Issue an HTTP POST and provide the data through the read callback.
+ * </DESC>
+ */
+#include <stdio.h>
+#include <string.h>
+#include <curl/curl.h>
+
+/* silly test data to POST */
+static const char data[]="Lorem ipsum dolor sit amet, consectetur adipiscing "
+  "elit. Sed vel urna neque. Ut quis leo metus. Quisque eleifend, ex at "
+  "laoreet rhoncus, odio ipsum semper metus, at tempus ante urna in mauris. "
+  "Suspendisse ornare tempor venenatis. Ut dui neque, pellentesque a varius "
+  "eget, mattis vitae ligula. Fusce ut pharetra est. Ut ullamcorper mi ac "
+  "sollicitudin semper. Praesent sit amet tellus varius, posuere nulla non, "
+  "rhoncus ipsum.";
+
+struct WriteThis {
+  const char *readptr;
+  size_t sizeleft;
+};
+
+static size_t read_callback(void *dest, size_t size, size_t nmemb, void *userp)
+{
+  struct WriteThis *wt = (struct WriteThis *)userp;
+  size_t buffer_size = size*nmemb;
+
+  if(wt->sizeleft) {
+    /* copy as much as possible from the source to the destination */
+    size_t copy_this_much = wt->sizeleft;
+    if(copy_this_much > buffer_size)
+      copy_this_much = buffer_size;
+    memcpy(dest, wt->readptr, copy_this_much);
+
+    wt->readptr += copy_this_much;
+    wt->sizeleft -= copy_this_much;
+    return copy_this_much; /* we copied this many bytes */
+  }
+
+  return 0; /* no more data left to deliver */
+}
+
+int main(void)
+{
+  CURL *curl;
+  CURLcode res;
+
+  struct WriteThis wt;
+
+  wt.readptr = data;
+  wt.sizeleft = strlen(data);
+
+  /* In windows, this will init the winsock stuff */
+  res = curl_global_init(CURL_GLOBAL_DEFAULT);
+  /* Check for errors */
+  if(res != CURLE_OK) {
+    fprintf(stderr, "curl_global_init() failed: %s\n",
+            curl_easy_strerror(res));
+    return 1;
+  }
+
+  /* get a curl handle */
+  curl = curl_easy_init();
+  if(curl) {
+    /* First set the URL that is about to receive our POST. */
+    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/index.cgi");
+
+    /* Now specify we want to POST data */
+    curl_easy_setopt(curl, CURLOPT_POST, 1L);
+
+    /* we want to use our own read function */
+    curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);
+
+    /* pointer to pass to our read function */
+    curl_easy_setopt(curl, CURLOPT_READDATA, &wt);
+
+    /* get verbose debug output please */
+    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
+
+    /*
+      If you use POST to a HTTP 1.1 server, you can send data without knowing
+      the size before starting the POST if you use chunked encoding. You
+      enable this by adding a header like "Transfer-Encoding: chunked" with
+      CURLOPT_HTTPHEADER. With HTTP 1.0 or without chunked transfer, you must
+      specify the size in the request.
+    */
+#ifdef USE_CHUNKED
+    {
+      struct curl_slist *chunk = NULL;
+
+      chunk = curl_slist_append(chunk, "Transfer-Encoding: chunked");
+      res = curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
+      /* use curl_slist_free_all() after the *perform() call to free this
+         list again */
+    }
+#else
+    /* Set the expected POST size. If you want to POST large amounts of data,
+       consider CURLOPT_POSTFIELDSIZE_LARGE */
+    curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, (long)wt.sizeleft);
+#endif
+
+#ifdef DISABLE_EXPECT
+    /*
+      Using POST with HTTP 1.1 implies the use of a "Expect: 100-continue"
+      header.  You can disable this header with CURLOPT_HTTPHEADER as usual.
+      NOTE: if you want chunked transfer too, you need to combine these two
+      since you can only set one list of headers with CURLOPT_HTTPHEADER. */
+
+    /* A less good option would be to enforce HTTP 1.0, but that might also
+       have other implications. */
+    {
+      struct curl_slist *chunk = NULL;
+
+      chunk = curl_slist_append(chunk, "Expect:");
+      res = curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
+      /* use curl_slist_free_all() after the *perform() call to free this
+         list again */
+    }
+#endif
+
+    /* Perform the request, res will get the return code */
+    res = curl_easy_perform(curl);
+    /* Check for errors */
+    if(res != CURLE_OK)
+      fprintf(stderr, "curl_easy_perform() failed: %s\n",
+              curl_easy_strerror(res));
+
+    /* always cleanup */
+    curl_easy_cleanup(curl);
+  }
+  curl_global_cleanup();
+  return 0;
+}