lavf: add samba protocol via libsmbclient

Signed-off-by: Lukasz Marek <lukasz.m.luki2@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/libsmbclient.c

@@ -0,0 +1,207 @@
+/*
+ * Copyright (c) 2014 Lukasz Marek <lukasz.m.luki@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <libsmbclient.h>
+#include "libavutil/avstring.h"
+#include "libavutil/opt.h"
+#include "avformat.h"
+#include "internal.h"
+#include "url.h"
+
+typedef struct {
+    const AVClass *class;
+    SMBCCTX *ctx;
+    int fd;
+    int64_t filesize;
+    int trunc;
+    int timeout;
+    char *workgroup;
+} LIBSMBContext;
+
+static void libsmbc_get_auth_data(SMBCCTX *c, const char *server, const char *share,
+                                  char *workgroup, int workgroup_len,
+                                  char *username, int username_len,
+                                  char *password, int password_len)
+{
+    /* Do nothing yet. Credentials are passed via url.
+     * Callback must exists, there might be a segmentation fault otherwise. */
+}
+
+static av_cold int libsmbc_connect(URLContext *h)
+{
+    LIBSMBContext *libsmbc = h->priv_data;
+
+    libsmbc->ctx = smbc_new_context();
+    if (!libsmbc->ctx) {
+        av_log(h, AV_LOG_ERROR, "Cannot create context: %s.\n", strerror(errno));
+        return AVERROR(errno);
+    }
+    if (!smbc_init_context(libsmbc->ctx)) {
+        av_log(h, AV_LOG_ERROR, "Cannot initialize context: %s.\n", strerror(errno));
+        return AVERROR(errno);
+    }
+    smbc_set_context(libsmbc->ctx);
+
+    smbc_setOptionUserData(libsmbc->ctx, h);
+    smbc_setFunctionAuthDataWithContext(libsmbc->ctx, libsmbc_get_auth_data);
+
+    if (libsmbc->timeout != -1)
+        smbc_setTimeout(libsmbc->ctx, libsmbc->timeout);
+    if (libsmbc->workgroup)
+        smbc_setWorkgroup(libsmbc->ctx, libsmbc->workgroup);
+
+    if (smbc_init(NULL, 0) < 0) {
+        av_log(h, AV_LOG_ERROR, "Initialization failed: %s\n", strerror(errno));
+        return AVERROR(errno);
+    }
+    return 0;
+}
+
+static av_cold int libsmbc_close(URLContext *h)
+{
+    LIBSMBContext *libsmbc = h->priv_data;
+    if (libsmbc->fd >= 0) {
+        smbc_close(libsmbc->fd);
+        libsmbc->fd = -1;
+    }
+    if (libsmbc->ctx) {
+        smbc_free_context(libsmbc->ctx, 1);
+        libsmbc->ctx = NULL;
+    }
+    return 0;
+}
+
+static av_cold int libsmbc_open(URLContext *h, const char *url, int flags)
+{
+    LIBSMBContext *libsmbc = h->priv_data;
+    int access, ret;
+    struct stat st;
+
+    libsmbc->fd = -1;
+    libsmbc->filesize = -1;
+
+    if ((ret = libsmbc_connect(h)) < 0)
+        goto fail;
+
+    if ((flags & AVIO_FLAG_WRITE) && (flags & AVIO_FLAG_READ)) {
+        access = O_CREAT | O_RDWR;
+        if (libsmbc->trunc)
+            access |= O_TRUNC;
+    } else if (flags & AVIO_FLAG_WRITE) {
+        access = O_CREAT | O_WRONLY;
+        if (libsmbc->trunc)
+            access |= O_TRUNC;
+    } else
+        access = O_RDONLY;
+
+    /* 0666 = -rw-rw-rw- = read+write for everyone, minus umask */
+    if ((libsmbc->fd = smbc_open(url, access, 0666)) < 0) {
+        ret = AVERROR(errno);
+        av_log(h, AV_LOG_ERROR, "File open failed: %s\n", strerror(errno));
+        goto fail;
+    }
+
+    if (smbc_fstat(libsmbc->fd, &st) < 0)
+        av_log(h, AV_LOG_WARNING, "Cannot stat file: %s\n", strerror(errno));
+    else
+        libsmbc->filesize = st.st_size;
+
+    return 0;
+  fail:
+    libsmbc_close(h);
+    return ret;
+}
+
+static int64_t libsmbc_seek(URLContext *h, int64_t pos, int whence)
+{
+    LIBSMBContext *libsmbc = h->priv_data;
+    int64_t newpos;
+
+    if (whence == AVSEEK_SIZE) {
+        if (libsmbc->filesize == -1) {
+            av_log(h, AV_LOG_ERROR, "Error during seeking: filesize is unknown.\n");
+            return AVERROR(EIO);
+        } else
+            return libsmbc->filesize;
+    }
+
+    if ((newpos = smbc_lseek(libsmbc->fd, pos, whence)) < 0) {
+        int err = errno;
+        av_log(h, AV_LOG_ERROR, "Error during seeking: %s\n", strerror(err));
+        return AVERROR(err);
+    }
+
+    return newpos;
+}
+
+static int libsmbc_read(URLContext *h, unsigned char *buf, int size)
+{
+    LIBSMBContext *libsmbc = h->priv_data;
+    int bytes_read;
+
+    if ((bytes_read = smbc_read(libsmbc->fd, buf, size)) < 0) {
+        av_log(h, AV_LOG_ERROR, "Read error: %s\n", strerror(errno));
+        return AVERROR(errno);
+    }
+
+    return bytes_read;
+}
+
+static int libsmbc_write(URLContext *h, const unsigned char *buf, int size)
+{
+    LIBSMBContext *libsmbc = h->priv_data;
+    int bytes_written;
+
+    if ((bytes_written = smbc_write(libsmbc->fd, buf, size)) < 0) {
+        av_log(h, AV_LOG_ERROR, "Write error: %s\n", strerror(errno));
+        return AVERROR(errno);
+    }
+
+    return bytes_written;
+}
+
+#define OFFSET(x) offsetof(LIBSMBContext, x)
+#define D AV_OPT_FLAG_DECODING_PARAM
+#define E AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption options[] = {
+    {"timeout",   "set timeout in ms of socket I/O operations",    OFFSET(timeout), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, D|E },
+    {"truncate",  "truncate existing files on write",              OFFSET(trunc),   AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
+    {"workgroup", "set the workgroup used for making connections", OFFSET(workgroup), AV_OPT_TYPE_STRING, { 0 }, 0, 0, D|E },
+    {NULL}
+};
+
+static const AVClass libsmbclient_context_class = {
+    .class_name     = "libsmbc",
+    .item_name      = av_default_item_name,
+    .option         = options,
+    .version        = LIBAVUTIL_VERSION_INT,
+};
+
+URLProtocol ff_libsmbclient_protocol = {
+    .name                = "smb",
+    .url_open            = libsmbc_open,
+    .url_read            = libsmbc_read,
+    .url_write           = libsmbc_write,
+    .url_seek            = libsmbc_seek,
+    .url_close           = libsmbc_close,
+    .priv_data_size      = sizeof(LIBSMBContext),
+    .priv_data_class     = &libsmbclient_context_class,
+    .flags               = URL_PROTOCOL_FLAG_NETWORK,
+};