init repo.

third_party/curl/lib/headers.c

@@ -0,0 +1,449 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  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
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+
+#include "urldata.h"
+#include "strdup.h"
+#include "strcase.h"
+#include "sendf.h"
+#include "headers.h"
+
+/* The last 3 #include files should be in this order */
+#include "curl_printf.h"
+#include "curl_memory.h"
+#include "memdebug.h"
+
+#if !defined(CURL_DISABLE_HTTP) && !defined(CURL_DISABLE_HEADERS_API)
+
+/* Generate the curl_header struct for the user. This function MUST assign all
+   struct fields in the output struct. */
+static void copy_header_external(struct Curl_header_store *hs,
+                                 size_t index,
+                                 size_t amount,
+                                 struct Curl_llist_element *e,
+                                 struct curl_header *hout)
+{
+  struct curl_header *h = hout;
+  h->name = hs->name;
+  h->value = hs->value;
+  h->amount = amount;
+  h->index = index;
+  /* this will randomly OR a reserved bit for the sole purpose of making it
+     impossible for applications to do == comparisons, as that would otherwise
+     be very tempting and then lead to the reserved bits not being reserved
+     anymore. */
+  h->origin = hs->type | (1<<27);
+  h->anchor = e;
+}
+
+/* public API */
+CURLHcode curl_easy_header(CURL *easy,
+                           const char *name,
+                           size_t nameindex,
+                           unsigned int type,
+                           int request,
+                           struct curl_header **hout)
+{
+  struct Curl_llist_element *e;
+  struct Curl_llist_element *e_pick = NULL;
+  struct Curl_easy *data = easy;
+  size_t match = 0;
+  size_t amount = 0;
+  struct Curl_header_store *hs = NULL;
+  struct Curl_header_store *pick = NULL;
+  if(!name || !hout || !data ||
+     (type > (CURLH_HEADER|CURLH_TRAILER|CURLH_CONNECT|CURLH_1XX|
+              CURLH_PSEUDO)) || !type || (request < -1))
+    return CURLHE_BAD_ARGUMENT;
+  if(!Curl_llist_count(&data->state.httphdrs))
+    return CURLHE_NOHEADERS; /* no headers available */
+  if(request > data->state.requests)
+    return CURLHE_NOREQUEST;
+  if(request == -1)
+    request = data->state.requests;
+
+  /* we need a first round to count amount of this header */
+  for(e = data->state.httphdrs.head; e; e = e->next) {
+    hs = e->ptr;
+    if(strcasecompare(hs->name, name) &&
+       (hs->type & type) &&
+       (hs->request == request)) {
+      amount++;
+      pick = hs;
+      e_pick = e;
+    }
+  }
+  if(!amount)
+    return CURLHE_MISSING;
+  else if(nameindex >= amount)
+    return CURLHE_BADINDEX;
+
+  if(nameindex == amount - 1)
+    /* if the last or only occurrence is what's asked for, then we know it */
+    hs = pick;
+  else {
+    for(e = data->state.httphdrs.head; e; e = e->next) {
+      hs = e->ptr;
+      if(strcasecompare(hs->name, name) &&
+         (hs->type & type) &&
+         (hs->request == request) &&
+         (match++ == nameindex)) {
+        e_pick = e;
+        break;
+      }
+    }
+    if(!e) /* this shouldn't happen */
+      return CURLHE_MISSING;
+  }
+  /* this is the name we want */
+  copy_header_external(hs, nameindex, amount, e_pick,
+                       &data->state.headerout[0]);
+  *hout = &data->state.headerout[0];
+  return CURLHE_OK;
+}
+
+/* public API */
+struct curl_header *curl_easy_nextheader(CURL *easy,
+                                         unsigned int type,
+                                         int request,
+                                         struct curl_header *prev)
+{
+  struct Curl_easy *data = easy;
+  struct Curl_llist_element *pick;
+  struct Curl_llist_element *e;
+  struct Curl_header_store *hs;
+  size_t amount = 0;
+  size_t index = 0;
+
+  if(request > data->state.requests)
+    return NULL;
+  if(request == -1)
+    request = data->state.requests;
+
+  if(prev) {
+    pick = prev->anchor;
+    if(!pick)
+      /* something is wrong */
+      return NULL;
+    pick = pick->next;
+  }
+  else
+    pick = data->state.httphdrs.head;
+
+  if(pick) {
+    /* make sure it is the next header of the desired type */
+    do {
+      hs = pick->ptr;
+      if((hs->type & type) && (hs->request == request))
+        break;
+      pick = pick->next;
+    } while(pick);
+  }
+
+  if(!pick)
+    /* no more headers available */
+    return NULL;
+
+  hs = pick->ptr;
+
+  /* count number of occurrences of this name within the mask and figure out
+     the index for the currently selected entry */
+  for(e = data->state.httphdrs.head; e; e = e->next) {
+    struct Curl_header_store *check = e->ptr;
+    if(strcasecompare(hs->name, check->name) &&
+       (check->request == request) &&
+       (check->type & type))
+      amount++;
+    if(e == pick)
+      index = amount - 1;
+  }
+
+  copy_header_external(hs, index, amount, pick,
+                       &data->state.headerout[1]);
+  return &data->state.headerout[1];
+}
+
+static CURLcode namevalue(char *header, size_t hlen, unsigned int type,
+                          char **name, char **value)
+{
+  char *end = header + hlen - 1; /* point to the last byte */
+  DEBUGASSERT(hlen);
+  *name = header;
+
+  if(type == CURLH_PSEUDO) {
+    if(*header != ':')
+      return CURLE_BAD_FUNCTION_ARGUMENT;
+    header++;
+  }
+
+  /* Find the end of the header name */
+  while(*header && (*header != ':'))
+    ++header;
+
+  if(*header)
+    /* Skip over colon, null it */
+    *header++ = 0;
+  else
+    return CURLE_BAD_FUNCTION_ARGUMENT;
+
+  /* skip all leading space letters */
+  while(*header && ISBLANK(*header))
+    header++;
+
+  *value = header;
+
+  /* skip all trailing space letters */
+  while((end > header) && ISSPACE(*end))
+    *end-- = 0; /* nul terminate */
+  return CURLE_OK;
+}
+
+static CURLcode unfold_value(struct Curl_easy *data, const char *value,
+                             size_t vlen)  /* length of the incoming header */
+{
+  struct Curl_header_store *hs;
+  struct Curl_header_store *newhs;
+  size_t olen; /* length of the old value */
+  size_t oalloc; /* length of the old name + value + separator */
+  size_t offset;
+  DEBUGASSERT(data->state.prevhead);
+  hs = data->state.prevhead;
+  olen = strlen(hs->value);
+  offset = hs->value - hs->buffer;
+  oalloc = olen + offset + 1;
+
+  /* skip all trailing space letters */
+  while(vlen && ISSPACE(value[vlen - 1]))
+    vlen--;
+
+  /* save only one leading space */
+  while((vlen > 1) && ISBLANK(value[0]) && ISBLANK(value[1])) {
+    vlen--;
+    value++;
+  }
+
+  /* since this header block might move in the realloc below, it needs to
+     first be unlinked from the list and then re-added again after the
+     realloc */
+  Curl_llist_remove(&data->state.httphdrs, &hs->node, NULL);
+
+  /* new size = struct + new value length + old name+value length */
+  newhs = Curl_saferealloc(hs, sizeof(*hs) + vlen + oalloc + 1);
+  if(!newhs)
+    return CURLE_OUT_OF_MEMORY;
+  /* ->name and ->value point into ->buffer (to keep the header allocation
+     in a single memory block), which now potentially have moved. Adjust
+     them. */
+  newhs->name = newhs->buffer;
+  newhs->value = &newhs->buffer[offset];
+
+  /* put the data at the end of the previous data, not the newline */
+  memcpy(&newhs->value[olen], value, vlen);
+  newhs->value[olen + vlen] = 0; /* null-terminate at newline */
+
+  /* insert this node into the list of headers */
+  Curl_llist_append(&data->state.httphdrs, newhs, &newhs->node);
+  data->state.prevhead = newhs;
+  return CURLE_OK;
+}
+
+
+/*
+ * Curl_headers_push() gets passed a full HTTP header to store. It gets called
+ * immediately before the header callback. The header is CRLF terminated.
+ */
+CURLcode Curl_headers_push(struct Curl_easy *data, const char *header,
+                           unsigned char type)
+{
+  char *value = NULL;
+  char *name = NULL;
+  char *end;
+  size_t hlen; /* length of the incoming header */
+  struct Curl_header_store *hs;
+  CURLcode result = CURLE_OUT_OF_MEMORY;
+
+  if((header[0] == '\r') || (header[0] == '\n'))
+    /* ignore the body separator */
+    return CURLE_OK;
+
+  end = strchr(header, '\r');
+  if(!end) {
+    end = strchr(header, '\n');
+    if(!end)
+      /* neither CR nor LF as terminator is not a valid header */
+      return CURLE_WEIRD_SERVER_REPLY;
+  }
+  hlen = end - header;
+
+  if((header[0] == ' ') || (header[0] == '\t')) {
+    if(data->state.prevhead)
+      /* line folding, append value to the previous header's value */
+      return unfold_value(data, header, hlen);
+    else {
+      /* Can't unfold without a previous header. Instead of erroring, just
+         pass the leading blanks. */
+      while(hlen && ISBLANK(*header)) {
+        header++;
+        hlen--;
+      }
+      if(!hlen)
+        return CURLE_WEIRD_SERVER_REPLY;
+    }
+  }
+
+  hs = calloc(1, sizeof(*hs) + hlen);
+  if(!hs)
+    return CURLE_OUT_OF_MEMORY;
+  memcpy(hs->buffer, header, hlen);
+  hs->buffer[hlen] = 0; /* nul terminate */
+
+  result = namevalue(hs->buffer, hlen, type, &name, &value);
+  if(!result) {
+    hs->name = name;
+    hs->value = value;
+    hs->type = type;
+    hs->request = data->state.requests;
+
+    /* insert this node into the list of headers */
+    Curl_llist_append(&data->state.httphdrs, hs, &hs->node);
+    data->state.prevhead = hs;
+  }
+  else
+    free(hs);
+  return result;
+}
+
+/*
+ * Curl_headers_reset(). Reset the headers subsystem.
+ */
+static void headers_reset(struct Curl_easy *data)
+{
+  Curl_llist_init(&data->state.httphdrs, NULL);
+  data->state.prevhead = NULL;
+}
+
+struct hds_cw_collect_ctx {
+  struct Curl_cwriter super;
+};
+
+static CURLcode hds_cw_collect_write(struct Curl_easy *data,
+                                     struct Curl_cwriter *writer, int type,
+                                     const char *buf, size_t blen)
+{
+  if((type & CLIENTWRITE_HEADER) && !(type & CLIENTWRITE_STATUS)) {
+    unsigned char htype = (unsigned char)
+      (type & CLIENTWRITE_CONNECT ? CURLH_CONNECT :
+       (type & CLIENTWRITE_1XX ? CURLH_1XX :
+        (type & CLIENTWRITE_TRAILER ? CURLH_TRAILER :
+         CURLH_HEADER)));
+    CURLcode result = Curl_headers_push(data, buf, htype);
+    CURL_TRC_WRITE(data, "header_collect pushed(type=%x, len=%zu) -> %d",
+                   htype, blen, result);
+    if(result)
+      return result;
+  }
+  return Curl_cwriter_write(data, writer->next, type, buf, blen);
+}
+
+static const struct Curl_cwtype hds_cw_collect = {
+  "hds-collect",
+  NULL,
+  Curl_cwriter_def_init,
+  hds_cw_collect_write,
+  Curl_cwriter_def_close,
+  sizeof(struct hds_cw_collect_ctx)
+};
+
+CURLcode Curl_headers_init(struct Curl_easy *data)
+{
+  struct Curl_cwriter *writer;
+  CURLcode result;
+
+  if(data->conn && (data->conn->handler->protocol & PROTO_FAMILY_HTTP)) {
+    /* avoid installing it twice */
+    if(Curl_cwriter_get_by_name(data, hds_cw_collect.name))
+      return CURLE_OK;
+
+    result = Curl_cwriter_create(&writer, data, &hds_cw_collect,
+                                 CURL_CW_PROTOCOL);
+    if(result)
+      return result;
+
+    result = Curl_cwriter_add(data, writer);
+    if(result) {
+      Curl_cwriter_free(data, writer);
+      return result;
+    }
+  }
+  return CURLE_OK;
+}
+
+/*
+ * Curl_headers_cleanup(). Free all stored headers and associated memory.
+ */
+CURLcode Curl_headers_cleanup(struct Curl_easy *data)
+{
+  struct Curl_llist_element *e;
+  struct Curl_llist_element *n;
+
+  for(e = data->state.httphdrs.head; e; e = n) {
+    struct Curl_header_store *hs = e->ptr;
+    n = e->next;
+    free(hs);
+  }
+  headers_reset(data);
+  return CURLE_OK;
+}
+
+#else /* HTTP-disabled builds below */
+
+CURLHcode curl_easy_header(CURL *easy,
+                           const char *name,
+                           size_t index,
+                           unsigned int origin,
+                           int request,
+                           struct curl_header **hout)
+{
+  (void)easy;
+  (void)name;
+  (void)index;
+  (void)origin;
+  (void)request;
+  (void)hout;
+  return CURLHE_NOT_BUILT_IN;
+}
+
+struct curl_header *curl_easy_nextheader(CURL *easy,
+                                         unsigned int type,
+                                         int request,
+                                         struct curl_header *prev)
+{
+  (void)easy;
+  (void)type;
+  (void)request;
+  (void)prev;
+  return NULL;
+}
+#endif