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 #include "compat.h"
  22
  23 struct http_response_s {
  24         int complete;
  25
  26         char *data;
  27         int data_size;
  28         int data_length;
  29 };
  30
  31
  32 static void
  33 http_response_add_data(http_response_t *response, const char *data, int datalen)
  34 {
  35         int newdatasize;
  36
  37         assert(response);
  38         assert(data);
  39         assert(datalen > 0);
  40
  41         newdatasize = response->data_size;
  42         while (response->data_size+datalen > newdatasize) {
  43                 newdatasize *= 2;
  44         }
  45         if (newdatasize != response->data_size) {
  46                 response->data = realloc(response->data, newdatasize);
  47                 assert(response->data);
  48         }
  49         memcpy(response->data+response->data_length, data, datalen);
  50         response->data_length += datalen;
  51 }
  52
  53 http_response_t *
  54 http_response_init(const char *protocol, int code, const char *message)
  55 {
  56         http_response_t *response;
  57         char codestr[4];
  58
  59         assert(code >= 100 && code < 1000);
  60
  61         /* Convert code into string */
  62         memset(codestr, 0, sizeof(codestr));
  63         snprintf(codestr, sizeof(codestr), "%u", code);
  64
  65         response = calloc(1, sizeof(http_response_t));
  66         if (!response) {
  67                 return NULL;
  68         }
  69
  70         /* Allocate response data */
  71         response->data_size = 1024;
  72         response->data = malloc(response->data_size);
  73         if (!response->data) {
  74                 free(response);
  75                 return NULL;
  76         }
  77
  78         /* Add first line of response to the data array */
  79         http_response_add_data(response, protocol, strlen(protocol));
  80         http_response_add_data(response, " ", 1);
  81         http_response_add_data(response, codestr, strlen(codestr));
  82         http_response_add_data(response, " ", 1);
  83         http_response_add_data(response, message, strlen(message));
  84         http_response_add_data(response, "\r\n", 2);
  85
  86         return response;
  87 }
  88
  89 void
  90 http_response_destroy(http_response_t *response)
  91 {
  92         if (response) {
  93                 free(response->data);
  94                 free(response);
  95         }
  96 }
  97
  98 void
  99 http_response_add_header(http_response_t *response, const char *name, const char *value)
 100 {
 101         assert(response);
 102         assert(name);
 103         assert(value);
 104
 105         http_response_add_data(response, name, strlen(name));
 106         http_response_add_data(response, ": ", 2);
 107         http_response_add_data(response, value, strlen(value));
 108         http_response_add_data(response, "\r\n", 2);
 109 }
 110
 111 void
 112 http_response_finish(http_response_t *response, const char *data, int datalen)
 113 {
 114         assert(response);
 115         assert(datalen==0 || (data && datalen > 0));
 116
 117         if (data && datalen > 0) {
 118                 const char *hdrname = "Content-Length";
 119                 char hdrvalue[16];
 120
 121                 memset(hdrvalue, 0, sizeof(hdrvalue));
 122                 snprintf(hdrvalue, sizeof(hdrvalue)-1, "%d", datalen);
 123
 124                 /* Add Content-Length header first */
 125                 http_response_add_data(response, hdrname, strlen(hdrname));
 126                 http_response_add_data(response, ": ", 2);
 127                 http_response_add_data(response, hdrvalue, strlen(hdrvalue));
 128                 http_response_add_data(response, "\r\n\r\n", 4);
 129
 130                 /* Add data to the end of response */
 131                 http_response_add_data(response, data, datalen);
 132         } else {
 133                 /* Add extra end of line after headers */
 134                 http_response_add_data(response, "\r\n", 2);
 135         }
 136         response->complete = 1;
 137 }
 138
 139 const char *
 140 http_response_get_data(http_response_t *response, int *datalen)
 141 {
 142         assert(response);
 143         assert(datalen);
 144         assert(response->complete);
 145
 146         *datalen = response->data_length;
 147         return response->data;
 148 }