src/lib/http_response.c

   1 /**
   2  *  Copyright (C) 2011-2012  Juho Vähä-Herttua
   3  *
   4  *  This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Lesser General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2.1 of the License, or (at your option) any later version.
   8  *
   9  *  This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Lesser General Public License for more details.
  13  */
  14
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <assert.h>
  19
  20 #include "http_response.h"
  21
  22 struct http_response_s {
  23         int complete;
  24
  25         char *data;
  26         int data_size;
  27         int data_length;
  28 };
  29
  30
  31 static void
  32 http_response_add_data(http_response_t *response, const char *data, int datalen)
  33 {
  34         int newdatasize;
  35
  36         assert(response);
  37         assert(data);
  38         assert(datalen > 0);
  39
  40         newdatasize = response->data_size;
  41         while (response->data_size+datalen > newdatasize) {
  42                 newdatasize *= 2;
  43         }
  44         if (newdatasize != response->data_size) {
  45                 response->data = realloc(response->data, newdatasize);
  46                 assert(response->data);
  47         }
  48         memcpy(response->data+response->data_length, data, datalen);
  49         response->data_length += datalen;
  50 }
  51
  52 http_response_t *
  53 http_response_init(const char *protocol, int code, const char *message)
  54 {
  55         http_response_t *response;
  56         char codestr[4];
  57
  58         assert(code >= 100 && code < 1000);
  59
  60         /* Convert code into string */
  61         memset(codestr, 0, sizeof(codestr));
  62         snprintf(codestr, sizeof(codestr), "%u", code);
  63
  64         response = calloc(1, sizeof(http_response_t));
  65         if (!response) {
  66                 return NULL;
  67         }
  68
  69         /* Allocate response data */
  70         response->data_size = 1024;
  71         response->data = malloc(response->data_size);
  72         if (!response->data) {
  73                 free(response);
  74                 return NULL;
  75         }
  76
  77         /* Add first line of response to the data array */
  78         http_response_add_data(response, protocol, strlen(protocol));
  79         http_response_add_data(response, " ", 1);
  80         http_response_add_data(response, codestr, strlen(codestr));
  81         http_response_add_data(response, " ", 1);
  82         http_response_add_data(response, message, strlen(message));
  83         http_response_add_data(response, "\r\n", 2);
  84
  85         return response;
  86 }
  87
  88 void
  89 http_response_destroy(http_response_t *response)
  90 {
  91         if (response) {
  92                 free(response->data);
  93                 free(response);
  94         }
  95 }
  96
  97 void
  98 http_response_add_header(http_response_t *response, const char *name, const char *value)
  99 {
 100         assert(response);
 101         assert(name);
 102         assert(value);
 103
 104         http_response_add_data(response, name, strlen(name));
 105         http_response_add_data(response, ": ", 2);
 106         http_response_add_data(response, value, strlen(value));
 107         http_response_add_data(response, "\r\n", 2);
 108 }
 109
 110 void
 111 http_response_finish(http_response_t *response, const char *data, int datalen)
 112 {
 113         assert(response);
 114         assert(datalen==0 || (data && datalen > 0));
 115
 116         if (data && datalen > 0) {
 117                 const char *hdrname = "Content-Length";
 118                 char hdrvalue[16];
 119
 120                 memset(hdrvalue, 0, sizeof(hdrvalue));
 121                 snprintf(hdrvalue, sizeof(hdrvalue)-1, "%d", datalen);
 122
 123                 /* Add Content-Length header first */
 124                 http_response_add_data(response, hdrname, strlen(hdrname));
 125                 http_response_add_data(response, ": ", 2);
 126                 http_response_add_data(response, hdrvalue, strlen(hdrvalue));
 127                 http_response_add_data(response, "\r\n\r\n", 4);
 128
 129                 /* Add data to the end of response */
 130                 http_response_add_data(response, data, datalen);
 131         } else {
 132                 /* Add extra end of line after headers */
 133                 http_response_add_data(response, "\r\n", 2);
 134         }
 135         response->complete = 1;
 136 }
 137
 138 const char *
 139 http_response_get_data(http_response_t *response, int *datalen)
 140 {
 141         assert(response);
 142         assert(datalen);
 143         assert(response->complete);
 144
 145         *datalen = response->data_length;
 146         return response->data;
 147 }