src/http_chunk.c

   1 #include "first.h"
   2
   3 /**
   4  * the HTTP chunk-API
   5  *
   6  *
   7  */
   8
   9 #include "server.h"
  10 #include "chunk.h"
  11 #include "http_chunk.h"
  12 #include "stat_cache.h"
  13 #include "log.h"
  14
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17
  18 #include <stdlib.h>
  19 #include <fcntl.h>
  20 #include <unistd.h>
  21
  22 #include <stdio.h>
  23 #include <errno.h>
  24 #include <string.h>
  25
  26 static void http_chunk_append_len(server *srv, connection *con, uintmax_t len) {
  27         buffer *b;
  28
  29         force_assert(NULL != srv);
  30
  31         b = srv->tmp_chunk_len;
  32
  33         buffer_string_set_length(b, 0);
  34         buffer_append_uint_hex(b, len);
  35         buffer_append_string_len(b, CONST_STR_LEN("\r\n"));
  36
  37         chunkqueue_append_buffer(con->write_queue, b);
  38 }
  39
  40 static int http_chunk_append_file_open_fstat(server *srv, connection *con, buffer *fn, struct stat *st) {
  41         if (!con->conf.follow_symlink) {
  42                 /*(preserve existing stat_cache symlink checks)*/
  43                 stat_cache_entry *sce;
  44                 if (HANDLER_ERROR == stat_cache_get_entry(srv, con, fn, &sce)) return -1;
  45         }
  46
  47         return stat_cache_open_rdonly_fstat(srv, con, fn, st);
  48 }
  49
  50 static void http_chunk_append_file_fd_range(server *srv, connection *con, buffer *fn, int fd, off_t offset, off_t len) {
  51         chunkqueue *cq = con->write_queue;
  52
  53         if (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) {
  54                 http_chunk_append_len(srv, con, (uintmax_t)len);
  55         }
  56
  57         chunkqueue_append_file_fd(cq, fn, fd, offset, len);
  58
  59         if (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) {
  60                 chunkqueue_append_mem(cq, CONST_STR_LEN("\r\n"));
  61         }
  62 }
  63
  64 int http_chunk_append_file_range(server *srv, connection *con, buffer *fn, off_t offset, off_t len) {
  65         struct stat st;
  66         const int fd = http_chunk_append_file_open_fstat(srv, con, fn, &st);
  67         if (fd < 0) return -1;
  68
  69         if (-1 == len) {
  70                 if (offset >= st.st_size) {
  71                         close(fd);
  72                         return (offset == st.st_size) ? 0 : -1;
  73                 }
  74                 len = st.st_size - offset;
  75         } else if (st.st_size - offset < len) {
  76                 close(fd);
  77                 return -1;
  78         }
  79
  80         http_chunk_append_file_fd_range(srv, con, fn, fd, offset, len);
  81         return 0;
  82 }
  83
  84 int http_chunk_append_file(server *srv, connection *con, buffer *fn) {
  85         struct stat st;
  86         const int fd = http_chunk_append_file_open_fstat(srv, con, fn, &st);
  87         if (fd < 0) return -1;
  88
  89         if (0 != st.st_size) {
  90                 http_chunk_append_file_fd_range(srv, con, fn, fd, 0, st.st_size);
  91         } else {
  92                 close(fd);
  93         }
  94         return 0;
  95 }
  96
  97 static int http_chunk_append_to_tempfile(server *srv, connection *con, const char * mem, size_t len) {
  98         chunkqueue * const cq = con->write_queue;
  99
 100         if (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) {
 101                 /*http_chunk_append_len(srv, con, len);*/
 102                 buffer *b = srv->tmp_chunk_len;
 103
 104                 buffer_string_set_length(b, 0);
 105                 buffer_append_uint_hex(b, len);
 106                 buffer_append_string_len(b, CONST_STR_LEN("\r\n"));
 107
 108                 if (0 != chunkqueue_append_mem_to_tempfile(srv, cq, CONST_BUF_LEN(b))) {
 109                         return -1;
 110                 }
 111         }
 112
 113         if (0 != chunkqueue_append_mem_to_tempfile(srv, cq, mem, len)) {
 114                 return -1;
 115         }
 116
 117         if (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) {
 118                 if (0 != chunkqueue_append_mem_to_tempfile(srv, cq, CONST_STR_LEN("\r\n"))) {
 119                         return -1;
 120                 }
 121         }
 122
 123         return 0;
 124 }
 125
 126 static int http_chunk_append_data(server *srv, connection *con, buffer *b, const char * mem, size_t len) {
 127
 128         chunkqueue * const cq = con->write_queue;
 129         chunk *c = cq->last;
 130         if (0 == len) return 0;
 131
 132         /* current usage does not append_mem or append_buffer after appending
 133          * file, so not checking if users of this interface have appended large
 134          * (references to) files to chunkqueue, which would not be in memory */
 135
 136         /*(allow slightly larger mem use if FDEVENT_STREAM_RESPONSE_BUFMIN
 137          * to reduce creation of temp files when backend producer will be
 138          * blocked until more data is sent to network to client)*/
 139
 140         if ((c && c->type == FILE_CHUNK && c->file.is_temp)
 141             || cq->bytes_in - cq->bytes_out + len
 142                 > 1024 * ((con->conf.stream_response_body & FDEVENT_STREAM_RESPONSE_BUFMIN) ? 128 : 64)) {
 143                 return http_chunk_append_to_tempfile(srv, con, b ? b->ptr : mem, len);
 144         }
 145
 146         /* not appending to prior mem chunk just in case using openssl
 147          * and need to resubmit same args as prior call to openssl (required?)*/
 148
 149         if (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) {
 150                 http_chunk_append_len(srv, con, len);
 151         }
 152
 153         /*(chunkqueue_append_buffer() might steal buffer contents)*/
 154         b ? chunkqueue_append_buffer(cq, b) : chunkqueue_append_mem(cq, mem, len);
 155
 156         if (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) {
 157                 chunkqueue_append_mem(cq, CONST_STR_LEN("\r\n"));
 158         }
 159
 160         return 0;
 161 }
 162
 163 int http_chunk_append_buffer(server *srv, connection *con, buffer *mem) {
 164         force_assert(NULL != con);
 165
 166         return http_chunk_append_data(srv, con, mem, NULL, buffer_string_length(mem));
 167 }
 168
 169 int http_chunk_append_mem(server *srv, connection *con, const char * mem, size_t len) {
 170         force_assert(NULL != con);
 171         force_assert(NULL != mem || 0 == len);
 172
 173         return http_chunk_append_data(srv, con, NULL, mem, len);
 174 }
 175
 176 void http_chunk_close(server *srv, connection *con) {
 177         UNUSED(srv);
 178         force_assert(NULL != con);
 179
 180         if (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) {
 181                 chunkqueue_append_mem(con->write_queue, CONST_STR_LEN("0\r\n\r\n"));
 182         }
 183 }