un-nest curl

curl-8.15.0/lib/escape.c

@@ -0,0 +1,236 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 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.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.
+ *
+ * SPDX-License-Identifier: curl
+ *
+ ***************************************************************************/
+
+/* Escape and unescape URL encoding in strings. The functions return a new
+ * allocated string or NULL if an error occurred.  */
+
+#include "curl_setup.h"
+
+#include <curl/curl.h>
+
+struct Curl_easy;
+
+#include "urldata.h"
+#include "curlx/warnless.h"
+#include "escape.h"
+#include "strdup.h"
+#include "curlx/strparse.h"
+
+/* The last 3 #include files should be in this order */
+#include "curl_printf.h"
+#include "curl_memory.h"
+#include "memdebug.h"
+
+/* for ABI-compatibility with previous versions */
+char *curl_escape(const char *string, int inlength)
+{
+  return curl_easy_escape(NULL, string, inlength);
+}
+
+/* for ABI-compatibility with previous versions */
+char *curl_unescape(const char *string, int length)
+{
+  return curl_easy_unescape(NULL, string, length, NULL);
+}
+
+/* Escapes for URL the given unescaped string of given length.
+ * 'data' is ignored since 7.82.0.
+ */
+char *curl_easy_escape(CURL *data, const char *string,
+                       int inlength)
+{
+  size_t length;
+  struct dynbuf d;
+  (void)data;
+
+  if(!string || (inlength < 0))
+    return NULL;
+
+  length = (inlength ? (size_t)inlength : strlen(string));
+  if(!length)
+    return strdup("");
+
+  curlx_dyn_init(&d, length * 3 + 1);
+
+  while(length--) {
+    /* treat the characters unsigned */
+    unsigned char in = (unsigned char)*string++;
+
+    if(ISUNRESERVED(in)) {
+      /* append this */
+      if(curlx_dyn_addn(&d, &in, 1))
+        return NULL;
+    }
+    else {
+      /* encode it */
+      unsigned char out[3]={'%'};
+      Curl_hexbyte(&out[1], in);
+      if(curlx_dyn_addn(&d, out, 3))
+        return NULL;
+    }
+  }
+
+  return curlx_dyn_ptr(&d);
+}
+
+/*
+ * Curl_urldecode() URL decodes the given string.
+ *
+ * Returns a pointer to a malloced string in *ostring with length given in
+ * *olen. If length == 0, the length is assumed to be strlen(string).
+ *
+ * ctrl options:
+ * - REJECT_NADA: accept everything
+ * - REJECT_CTRL: rejects control characters (byte codes lower than 32) in
+ *                the data
+ * - REJECT_ZERO: rejects decoded zero bytes
+ *
+ * The values for the enum starts at 2, to make the assert detect legacy
+ * invokes that used TRUE/FALSE (0 and 1).
+ */
+
+CURLcode Curl_urldecode(const char *string, size_t length,
+                        char **ostring, size_t *olen,
+                        enum urlreject ctrl)
+{
+  size_t alloc;
+  char *ns;
+
+  DEBUGASSERT(string);
+  DEBUGASSERT(ctrl >= REJECT_NADA); /* crash on TRUE/FALSE */
+
+  alloc = (length ? length : strlen(string));
+  ns = malloc(alloc + 1);
+
+  if(!ns)
+    return CURLE_OUT_OF_MEMORY;
+
+  /* store output string */
+  *ostring = ns;
+
+  while(alloc) {
+    unsigned char in = (unsigned char)*string;
+    if(('%' == in) && (alloc > 2) &&
+       ISXDIGIT(string[1]) && ISXDIGIT(string[2])) {
+      /* this is two hexadecimal digits following a '%' */
+      in = (unsigned char)((Curl_hexval(string[1]) << 4) |
+                           Curl_hexval(string[2]));
+      string += 3;
+      alloc -= 3;
+    }
+    else {
+      string++;
+      alloc--;
+    }
+
+    if(((ctrl == REJECT_CTRL) && (in < 0x20)) ||
+       ((ctrl == REJECT_ZERO) && (in == 0))) {
+      Curl_safefree(*ostring);
+      return CURLE_URL_MALFORMAT;
+    }
+
+    *ns++ = (char)in;
+  }
+  *ns = 0; /* terminate it */
+
+  if(olen)
+    /* store output size */
+    *olen = ns - *ostring;
+
+  return CURLE_OK;
+}
+
+/*
+ * Unescapes the given URL escaped string of given length. Returns a
+ * pointer to a malloced string with length given in *olen.
+ * If length == 0, the length is assumed to be strlen(string).
+ * If olen == NULL, no output length is stored.
+ * 'data' is ignored since 7.82.0.
+ */
+char *curl_easy_unescape(CURL *data, const char *string,
+                         int length, int *olen)
+{
+  char *str = NULL;
+  (void)data;
+  if(string && (length >= 0)) {
+    size_t inputlen = (size_t)length;
+    size_t outputlen;
+    CURLcode res = Curl_urldecode(string, inputlen, &str, &outputlen,
+                                  REJECT_NADA);
+    if(res)
+      return NULL;
+
+    if(olen) {
+      if(outputlen <= (size_t) INT_MAX)
+        *olen = curlx_uztosi(outputlen);
+      else
+        /* too large to return in an int, fail! */
+        Curl_safefree(str);
+    }
+  }
+  return str;
+}
+
+/* For operating systems/environments that use different malloc/free
+   systems for the app and for this library, we provide a free that uses
+   the library's memory system */
+void curl_free(void *p)
+{
+  free(p);
+}
+
+/*
+ * Curl_hexencode()
+ *
+ * Converts binary input to lowercase hex-encoded ASCII output.
+ * Null-terminated.
+ */
+void Curl_hexencode(const unsigned char *src, size_t len, /* input length */
+                    unsigned char *out, size_t olen) /* output buffer size */
+{
+  DEBUGASSERT(src && len && (olen >= 3));
+  if(src && len && (olen >= 3)) {
+    while(len-- && (olen >= 3)) {
+      out[0] = Curl_ldigits[*src >> 4];
+      out[1] = Curl_ldigits[*src & 0x0F];
+      ++src;
+      out += 2;
+      olen -= 2;
+    }
+    *out = 0;
+  }
+  else if(olen)
+    *out = 0;
+}
+
+/* Curl_hexbyte
+ *
+ * Output a single unsigned char as a two-digit UPPERCASE hex number.
+ */
+void Curl_hexbyte(unsigned char *dest, /* must fit two bytes */
+                  unsigned char val)
+{
+  dest[0] = Curl_udigits[val >> 4];
+  dest[1] = Curl_udigits[val & 0x0F];
+}