ffmpeg/libavformat/libsmbclient.c

   1 /*
   2  * Copyright (c) 2014 Lukasz Marek <lukasz.m.luki@gmail.com>
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <libsmbclient.h>
  22 #include "libavutil/avstring.h"
  23 #include "libavutil/opt.h"
  24 #include "avformat.h"
  25 #include "internal.h"
  26 #include "url.h"
  27
  28 typedef struct {
  29     const AVClass *class;
  30     SMBCCTX *ctx;
  31     int fd;
  32     int64_t filesize;
  33     int trunc;
  34     int timeout;
  35     char *workgroup;
  36 } LIBSMBContext;
  37
  38 static void libsmbc_get_auth_data(SMBCCTX *c, const char *server, const char *share,
  39                                   char *workgroup, int workgroup_len,
  40                                   char *username, int username_len,
  41                                   char *password, int password_len)
  42 {
  43     /* Do nothing yet. Credentials are passed via url.
  44      * Callback must exists, there might be a segmentation fault otherwise. */
  45 }
  46
  47 static av_cold int libsmbc_connect(URLContext *h)
  48 {
  49     LIBSMBContext *libsmbc = h->priv_data;
  50
  51     libsmbc->ctx = smbc_new_context();
  52     if (!libsmbc->ctx) {
  53         int ret = AVERROR(errno);
  54         av_log(h, AV_LOG_ERROR, "Cannot create context: %s.\n", strerror(errno));
  55         return ret;
  56     }
  57     if (!smbc_init_context(libsmbc->ctx)) {
  58         int ret = AVERROR(errno);
  59         av_log(h, AV_LOG_ERROR, "Cannot initialize context: %s.\n", strerror(errno));
  60         return ret;
  61     }
  62     smbc_set_context(libsmbc->ctx);
  63
  64     smbc_setOptionUserData(libsmbc->ctx, h);
  65     smbc_setFunctionAuthDataWithContext(libsmbc->ctx, libsmbc_get_auth_data);
  66
  67     if (libsmbc->timeout != -1)
  68         smbc_setTimeout(libsmbc->ctx, libsmbc->timeout);
  69     if (libsmbc->workgroup)
  70         smbc_setWorkgroup(libsmbc->ctx, libsmbc->workgroup);
  71
  72     if (smbc_init(NULL, 0) < 0) {
  73         int ret = AVERROR(errno);
  74         av_log(h, AV_LOG_ERROR, "Initialization failed: %s\n", strerror(errno));
  75         return ret;
  76     }
  77     return 0;
  78 }
  79
  80 static av_cold int libsmbc_close(URLContext *h)
  81 {
  82     LIBSMBContext *libsmbc = h->priv_data;
  83     if (libsmbc->fd >= 0) {
  84         smbc_close(libsmbc->fd);
  85         libsmbc->fd = -1;
  86     }
  87     if (libsmbc->ctx) {
  88         smbc_free_context(libsmbc->ctx, 1);
  89         libsmbc->ctx = NULL;
  90     }
  91     return 0;
  92 }
  93
  94 static av_cold int libsmbc_open(URLContext *h, const char *url, int flags)
  95 {
  96     LIBSMBContext *libsmbc = h->priv_data;
  97     int access, ret;
  98     struct stat st;
  99
 100     libsmbc->fd = -1;
 101     libsmbc->filesize = -1;
 102
 103     if ((ret = libsmbc_connect(h)) < 0)
 104         goto fail;
 105
 106     if ((flags & AVIO_FLAG_WRITE) && (flags & AVIO_FLAG_READ)) {
 107         access = O_CREAT | O_RDWR;
 108         if (libsmbc->trunc)
 109             access |= O_TRUNC;
 110     } else if (flags & AVIO_FLAG_WRITE) {
 111         access = O_CREAT | O_WRONLY;
 112         if (libsmbc->trunc)
 113             access |= O_TRUNC;
 114     } else
 115         access = O_RDONLY;
 116
 117     /* 0666 = -rw-rw-rw- = read+write for everyone, minus umask */
 118     if ((libsmbc->fd = smbc_open(url, access, 0666)) < 0) {
 119         ret = AVERROR(errno);
 120         av_log(h, AV_LOG_ERROR, "File open failed: %s\n", strerror(errno));
 121         goto fail;
 122     }
 123
 124     if (smbc_fstat(libsmbc->fd, &st) < 0)
 125         av_log(h, AV_LOG_WARNING, "Cannot stat file: %s\n", strerror(errno));
 126     else
 127         libsmbc->filesize = st.st_size;
 128
 129     return 0;
 130   fail:
 131     libsmbc_close(h);
 132     return ret;
 133 }
 134
 135 static int64_t libsmbc_seek(URLContext *h, int64_t pos, int whence)
 136 {
 137     LIBSMBContext *libsmbc = h->priv_data;
 138     int64_t newpos;
 139
 140     if (whence == AVSEEK_SIZE) {
 141         if (libsmbc->filesize == -1) {
 142             av_log(h, AV_LOG_ERROR, "Error during seeking: filesize is unknown.\n");
 143             return AVERROR(EIO);
 144         } else
 145             return libsmbc->filesize;
 146     }
 147
 148     if ((newpos = smbc_lseek(libsmbc->fd, pos, whence)) < 0) {
 149         int err = errno;
 150         av_log(h, AV_LOG_ERROR, "Error during seeking: %s\n", strerror(err));
 151         return AVERROR(err);
 152     }
 153
 154     return newpos;
 155 }
 156
 157 static int libsmbc_read(URLContext *h, unsigned char *buf, int size)
 158 {
 159     LIBSMBContext *libsmbc = h->priv_data;
 160     int bytes_read;
 161
 162     if ((bytes_read = smbc_read(libsmbc->fd, buf, size)) < 0) {
 163         int ret = AVERROR(errno);
 164         av_log(h, AV_LOG_ERROR, "Read error: %s\n", strerror(errno));
 165         return ret;
 166     }
 167
 168     return bytes_read;
 169 }
 170
 171 static int libsmbc_write(URLContext *h, const unsigned char *buf, int size)
 172 {
 173     LIBSMBContext *libsmbc = h->priv_data;
 174     int bytes_written;
 175
 176     if ((bytes_written = smbc_write(libsmbc->fd, buf, size)) < 0) {
 177         int ret = AVERROR(errno);
 178         av_log(h, AV_LOG_ERROR, "Write error: %s\n", strerror(errno));
 179         return ret;
 180     }
 181
 182     return bytes_written;
 183 }
 184
 185 #define OFFSET(x) offsetof(LIBSMBContext, x)
 186 #define D AV_OPT_FLAG_DECODING_PARAM
 187 #define E AV_OPT_FLAG_ENCODING_PARAM
 188 static const AVOption options[] = {
 189     {"timeout",   "set timeout in ms of socket I/O operations",    OFFSET(timeout), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, D|E },
 190     {"truncate",  "truncate existing files on write",              OFFSET(trunc),   AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
 191     {"workgroup", "set the workgroup used for making connections", OFFSET(workgroup), AV_OPT_TYPE_STRING, { 0 }, 0, 0, D|E },
 192     {NULL}
 193 };
 194
 195 static const AVClass libsmbclient_context_class = {
 196     .class_name     = "libsmbc",
 197     .item_name      = av_default_item_name,
 198     .option         = options,
 199     .version        = LIBAVUTIL_VERSION_INT,
 200 };
 201
 202 URLProtocol ff_libsmbclient_protocol = {
 203     .name                = "smb",
 204     .url_open            = libsmbc_open,
 205     .url_read            = libsmbc_read,
 206     .url_write           = libsmbc_write,
 207     .url_seek            = libsmbc_seek,
 208     .url_close           = libsmbc_close,
 209     .priv_data_size      = sizeof(LIBSMBContext),
 210     .priv_data_class     = &libsmbclient_context_class,
 211     .flags               = URL_PROTOCOL_FLAG_NETWORK,
 212 };