uclient-example.c

   1 /*
   2  * uclient - ustream based protocol client library
   3  *
   4  * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <unistd.h>
  20 #include <stdio.h>
  21 #include <dlfcn.h>
  22 #include <getopt.h>
  23 #include <fcntl.h>
  24
  25 #include <libubox/blobmsg.h>
  26
  27 #include "uclient.h"
  28
  29 #ifdef __APPLE__
  30 #define LIB_EXT "dylib"
  31 #else
  32 #define LIB_EXT "so"
  33 #endif
  34
  35 static struct ustream_ssl_ctx *ssl_ctx;
  36 static const struct ustream_ssl_ops *ssl_ops;
  37 static int quiet = false;
  38 static const char *output_file;
  39 static int output_fd;
  40 static int error_ret;
  41
  42 static int open_output_file(const char *path, bool create)
  43 {
  44         const char *str;
  45         char *filename;
  46         int len;
  47         int flags = O_WRONLY;
  48
  49         if (create)
  50                 flags |= O_CREAT;
  51
  52         if (output_file) {
  53                 if (!strcmp(output_file, "-"))
  54                         return STDOUT_FILENO;
  55
  56                 return open(output_file, flags, 0644);
  57         }
  58
  59         /* Don't automatically overwrite files if the name is derived from the URL */
  60         if (create)
  61                 flags |= O_EXCL;
  62
  63         len = strcspn(path, ";&");
  64         while (len > 0 && path[len - 1] == '/')
  65                 len--;
  66
  67         for (str = path + len - 1; str >= path; str--) {
  68                 if (*str == '/')
  69                         break;
  70         }
  71
  72         str++;
  73         len -= str - path;
  74
  75         if (len > 0) {
  76                 filename = alloca(len + 1);
  77                 strncpy(filename, str, len);
  78                 filename[len] = 0;
  79         } else {
  80                 filename = "index.html";
  81         }
  82
  83         return open(filename, flags, 0644);
  84 }
  85
  86 static void example_header_done(struct uclient *cl)
  87 {
  88         struct blob_attr *cur;
  89         int rem;
  90
  91         if (quiet)
  92                 return;
  93
  94         printf("Headers (%d): \n", cl->status_code);
  95         blobmsg_for_each_attr(cur, cl->meta, rem) {
  96                 printf("%s=%s\n", blobmsg_name(cur), (char *) blobmsg_data(cur));
  97         }
  98
  99         output_fd = open_output_file(cl->url->location, true);
 100         if (output_fd < 0) {
 101                 if (!quiet) {
 102                         perror("Cannot open output file");
 103                         error_ret = 3;
 104                         uloop_end();
 105                 }
 106         }
 107 }
 108
 109 static void example_read_data(struct uclient *cl)
 110 {
 111         char buf[256];
 112         int len;
 113
 114         if (error_ret)
 115                 return;
 116
 117         while (1) {
 118                 len = uclient_read(cl, buf, sizeof(buf));
 119                 if (!len)
 120                         return;
 121
 122                 write(output_fd, buf, len);
 123         }
 124 }
 125
 126 static void msg_connecting(struct uclient *cl)
 127 {
 128         char addr[INET6_ADDRSTRLEN];
 129         int port;
 130
 131         if (quiet)
 132                 return;
 133
 134         uclient_get_addr(addr, &port, &cl->remote_addr);
 135         fprintf(stderr, "Connecting to %s %s:%d\n", cl->url->host, addr, port);
 136 }
 137
 138 static void init_request(struct uclient *cl)
 139 {
 140         uclient_connect(cl);
 141         msg_connecting(cl);
 142         uclient_http_set_request_type(cl, "GET");
 143         uclient_request(cl);
 144 }
 145
 146 static void request_done(struct uclient *cl)
 147 {
 148         uloop_end();
 149 }
 150
 151 static void example_eof(struct uclient *cl)
 152 {
 153         static int retries;
 154
 155         if (retries < 10 && uclient_http_redirect(cl)) {
 156                 retries++;
 157                 return;
 158         }
 159
 160         retries = 0;
 161         request_done(cl);
 162 }
 163
 164 static void example_error(struct uclient *cl, int code)
 165 {
 166         if (!quiet)
 167                 fprintf(stderr, "Error %d!\n", code);
 168
 169         request_done(cl);
 170 }
 171
 172 static const struct uclient_cb cb = {
 173         .header_done = example_header_done,
 174         .data_read = example_read_data,
 175         .data_eof = example_eof,
 176         .error = example_error,
 177 };
 178
 179 static int usage(const char *progname)
 180 {
 181         fprintf(stderr,
 182                 "Usage: %s [options] <URL>\n"
 183                 "Options:\n"
 184                 "\n"
 185                 "HTTPS options:\n"
 186                 "       --ca-certificate=<cert>:        Load CA certificates from file <cert>\n"
 187                 "       --no-check-certificate:         don't validate the server's certificate\n"
 188                 "\n", progname);
 189         return 1;
 190 }
 191
 192
 193 static void init_ustream_ssl(void)
 194 {
 195         void *dlh;
 196
 197         dlh = dlopen("libustream-ssl." LIB_EXT, RTLD_LAZY | RTLD_LOCAL);
 198         if (!dlh)
 199                 return;
 200
 201         ssl_ops = dlsym(dlh, "ustream_ssl_ops");
 202         if (!ssl_ops)
 203                 return;
 204
 205         ssl_ctx = ssl_ops->context_new(false);
 206 }
 207
 208 static int no_ssl(const char *progname)
 209 {
 210         fprintf(stderr, "%s: SSL support not available, please install ustream-ssl\n", progname);
 211         return 1;
 212 }
 213
 214 enum {
 215         L_NO_CHECK_CERTIFICATE,
 216         L_CA_CERTIFICATE,
 217 };
 218
 219 static const struct option longopts[] = {
 220         [L_NO_CHECK_CERTIFICATE] = { "no-check-certificate", no_argument },
 221         [L_CA_CERTIFICATE] = { "ca-certificate", required_argument },
 222         {}
 223 };
 224
 225 int main(int argc, char **argv)
 226 {
 227         const char *progname = argv[0];
 228         struct uclient *cl;
 229         bool verify = true;
 230         int ch;
 231         int longopt_idx = 0;
 232
 233         init_ustream_ssl();
 234
 235         while ((ch = getopt_long(argc, argv, "qO:", longopts, &longopt_idx)) != -1) {
 236                 switch(ch) {
 237                 case 0:
 238                         switch (longopt_idx) {
 239                         case L_NO_CHECK_CERTIFICATE:
 240                                 verify = false;
 241                                 break;
 242                         case L_CA_CERTIFICATE:
 243                                 if (ssl_ctx)
 244                                         ssl_ops->context_add_ca_crt_file(ssl_ctx, optarg);
 245                                 break;
 246                         default:
 247                                 return usage(progname);
 248                         }
 249                         break;
 250                 case 'O':
 251                         output_file = optarg;
 252                         break;
 253                 case 'q':
 254                         quiet = true;
 255                         break;
 256                 default:
 257                         return usage(progname);
 258                 }
 259         }
 260
 261         argv += optind;
 262         argc -= optind;
 263
 264         if (argc != 1)
 265                 return usage(progname);
 266
 267         if (!strncmp(argv[0], "https", 5) && !ssl_ctx)
 268                 return no_ssl(progname);
 269
 270         uloop_init();
 271
 272         cl = uclient_new(argv[0], NULL, &cb);
 273         if (!cl) {
 274                 fprintf(stderr, "Failed to allocate uclient context\n");
 275                 return 1;
 276         }
 277
 278         if (ssl_ctx)
 279                 uclient_http_set_ssl_ctx(cl, ssl_ops, ssl_ctx, verify);
 280
 281         init_request(cl);
 282         uloop_run();
 283         uloop_done();
 284
 285         uclient_free(cl);
 286
 287         if (ssl_ctx)
 288                 ssl_ops->context_free(ssl_ctx);
 289
 290         return error_ret;
 291 }