Backport dump filter

modules/access_filter/Modules.am

 SOURCES_access_filter_timeshift = timeshift.c
 SOURCES_access_filter_record = record.c
+SOURCES_access_filter_dump = dump.c

modules/access_filter/dump.c

+/*****************************************************************************
+ * dump.c
+ *****************************************************************************
+ * Copyright © 2006 Rémi Denis-Courmont
+ * $Id$
+ *
+ * Author: Rémi Denis-Courmont <rem # videolan,org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#include <vlc/vlc.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <time.h>
+#include <errno.h>
+
+#include "vlc_access.h"
+#include "vlc_block.h"
+#include "charset.h"
+#include "vlc_keys.h"
+
+#define DEFAULT_MARGIN 32 // megabytes
+
+#define FORCE_TEXT N_("Force use of dump module")
+#define FORCE_LONGTEXT N_("Activate the dump module " \
+                          "even for media with fast seeking.")
+
+#define MARGIN_TEXT N_("Maximum size of temporary file (Mb)")
+#define MARGIN_LONGTEXT N_("The dump module will abort dumping of the media " \
+                           "if more than this much megabyte were performed.")
+
+static int  Open (vlc_object_t *);
+static void Close (vlc_object_t *);
+
+vlc_module_begin ();
+    set_shortname (_("Dump"));
+    set_description (_("Dump"));
+    set_category (CAT_INPUT);
+    set_subcategory (SUBCAT_INPUT_ACCESS_FILTER);
+    set_capability ("access_filter", 0);
+    add_shortcut ("dump");
+    set_callbacks (Open, Close);
+
+    add_bool ("dump-force", VLC_FALSE, NULL, FORCE_TEXT,
+              FORCE_LONGTEXT, VLC_FALSE);
+    add_integer ("dump-margin", DEFAULT_MARGIN, NULL, MARGIN_TEXT,
+                 MARGIN_LONGTEXT, VLC_FALSE);
+vlc_module_end();
+
+static int Read (access_t *access, uint8_t *buffer, int len);
+static block_t *Block (access_t *access);
+static int Seek (access_t *access, int64_t offset);
+static int Control (access_t *access, int cmd, va_list ap);
+
+static void Trigger (access_t *access);
+static int KeyHandler (vlc_object_t *obj, char const *varname,
+                       vlc_value_t oldval, vlc_value_t newval, void *data);
+
+struct access_sys_t
+{
+    FILE *stream;
+    int64_t tmp_max;
+    int64_t dumpsize;
+};
+
+/**
+ * Open()
+ */
+static int Open (vlc_object_t *obj)
+{
+    access_t *access = (access_t*)obj;
+    access_t *src = access->p_source;
+
+    if (!var_CreateGetBool (access, "dump-force"))
+    {
+        vlc_bool_t b;
+        if ((access2_Control (src, ACCESS_CAN_FASTSEEK, &b) == 0) && b)
+        {
+            msg_Dbg (obj, "dump filter useless");
+            return VLC_EGENERIC;
+        }
+    }
+
+    if (src->pf_read != NULL)
+        access->pf_read = Read;
+    else
+        access->pf_block = Block;
+    if (src->pf_seek != NULL)
+        access->pf_seek = Seek;
+
+    access->pf_control = Control;
+    access->info = src->info;
+
+    access_sys_t *p_sys = access->p_sys = malloc (sizeof (*p_sys));
+    if (p_sys == NULL)
+        return VLC_ENOMEM;
+    memset (p_sys, 0, sizeof (*p_sys));
+
+    if ((p_sys->stream = tmpfile ()) == NULL)
+    {
+        msg_Err (access, "cannot create temporary file: %s", strerror (errno));
+        free (p_sys);
+        return VLC_EGENERIC;
+    }
+    p_sys->tmp_max = ((int64_t)var_CreateGetInteger (access, "dump-margin")) << 20;
+
+    var_AddCallback (access->p_libvlc, "key-pressed", KeyHandler, access);
+
+    return VLC_SUCCESS;
+}
+
+
+/**
+ * Close()
+ */
+static void Close (vlc_object_t *obj)
+{
+    access_t *access = (access_t *)obj;
+    access_sys_t *p_sys = access->p_sys;
+
+    var_DelCallback (access->p_libvlc, "key-pressed", KeyHandler, access);
+
+    if (p_sys->stream != NULL)
+        fclose (p_sys->stream);
+    free (p_sys);
+}
+
+
+static void Dump (access_t *access, const uint8_t *buffer, size_t len)
+{
+    access_sys_t *p_sys = access->p_sys;
+    FILE *stream = p_sys->stream;
+
+    if ((stream == NULL) /* not dumping */
+     || (access->info.i_pos < p_sys->dumpsize) /* already known data */)
+        return;
+
+    size_t needed = access->info.i_pos - p_sys->dumpsize;
+    if (len < needed)
+        return; /* gap between data and dump offset (seek too far ahead?) */
+
+    buffer += len - needed;
+    len = needed;
+
+    if (len == 0)
+        return; /* no useful data */
+
+    if ((p_sys->tmp_max != -1) && (access->info.i_pos > p_sys->tmp_max))
+    {
+        msg_Dbg (access, "too much data - dump will not work");
+        goto error;
+    }
+
+    assert (len > 0);
+    if (fwrite (buffer, len, 1, stream) != 1)
+    {
+        msg_Err (access, "cannot write to file: %s", strerror (errno));
+        goto error;
+    }
+
+    p_sys->dumpsize += len;
+    return;
+
+error:
+    fclose (stream);
+    p_sys->stream = NULL;
+}
+
+
+static int Read (access_t *access, uint8_t *buffer, int len)
+{
+    access_t *src = access->p_source;
+
+    src->info.i_update = access->info.i_update;
+    len = src->pf_read (src, buffer, len);
+    access->info = src->info;
+
+    Dump (access, buffer, len);
+
+    return len;
+}
+
+
+static block_t *Block (access_t *access)
+{
+    access_t *src = access->p_source;
+    block_t *block;
+
+    src->info.i_update = access->info.i_update;
+    block = src->pf_block (src);
+    access->info = src->info;
+
+    if ((block == NULL) || (block->i_buffer <= 0))
+        return block;
+
+    Dump (access, block->p_buffer, block->i_buffer);
+
+    return block;
+}
+
+
+static int Control (access_t *access, int cmd, va_list ap)
+{
+    access_t *src = access->p_source;
+
+    return src->pf_control (src, cmd, ap);
+}
+
+
+static int Seek (access_t *access, int64_t offset)
+{
+    access_t *src = access->p_source;
+    access_sys_t *p_sys = access->p_sys;
+
+    if (p_sys->tmp_max == -1)
+    {
+        msg_Err (access, "cannot seek while dumping!");
+        return VLC_EGENERIC;
+    }
+
+    if (p_sys->stream != NULL)
+        msg_Dbg (access, "seeking - dump might not work");
+
+    src->info.i_update = access->info.i_update;
+    int ret = src->pf_seek (src, offset);
+    access->info = src->info;
+    return ret;
+}
+
+
+#ifndef HAVE_LOCALTIME_R
+static inline struct tm *localtime_r (const time_t *now, struct tm *res)
+{
+    struct tm *unsafe = localtime (now);
+    /*
+     * This is not thread-safe. Blame your C library.
+     * On Win32 there SHOULD be _localtime_s instead, but of course
+     * Cygwin and Mingw32 don't know about it. You're on your own if you
+     * this platform.
+     */
+    if (unsafe == NULL)
+        return NULL;
+
+    memcpy (res, unsafe, sizeof (*res));
+    return res;
+}
+#endif
+
+
+static void Trigger (access_t *access)
+{
+    access_sys_t *p_sys = access->p_sys;
+
+    if (p_sys->stream == NULL)
+        return; // too late
+
+    if (p_sys->tmp_max == -1)
+        return; // already triggered - should we stop? FIXME
+
+    time_t now;
+    time (&now);
+
+    struct tm t;
+    if (localtime_r (&now, &t) == NULL)
+        return; // No time, eh? Well, I'd rather not run on your computer.
+
+    if (t.tm_year > 999999999)
+        // Humanity is about 300 times older than when this was written,
+        // and there is an off-by-one in the following sprintf().
+        return;
+
+    const char *home = access->p_libvlc->psz_homedir;
+
+    /* Hmm what about the extension?? */
+    char filename[strlen (home) + sizeof ("/vlcdump-YYYYYYYYY-MM-DD-HH-MM-SS.ts")];
+    sprintf (filename, "%s/vlcdump-%04u-%02u-%02u-%02u-%02u-%02u.ts", home,
+             t.tm_year, t.tm_mon, t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec);
+
+    msg_Info (access, "dumping media to \"%s\"...", filename);
+
+    FILE *newstream = fopen (filename, "wb");
+    if (newstream == NULL)
+    {
+        msg_Err (access, "cannot create dump file \"%s\": %s", filename,
+                 strerror (errno));
+        return;
+    }
+
+    /* This might cause excessive hard drive work :( */
+    FILE *oldstream = p_sys->stream;
+    rewind (oldstream);
+
+    for (;;)
+    {
+        char buf[16384];
+        size_t len = fread (buf, 1, sizeof (buf), oldstream);
+        if (len == 0)
+        {
+            if (ferror (oldstream))
+            {
+                msg_Err (access, "cannot read temporary file: %s",
+                         strerror (errno));
+                break;
+            }
+
+            /* Done with temporary file */
+            fclose (oldstream);
+            p_sys->stream = newstream;
+            p_sys->tmp_max = -1;
+            return;
+        }
+
+        if (fwrite (buf, len, 1, newstream) != 1)
+        {
+            msg_Err (access, "cannot write dump file: %s", strerror (errno));
+            break;
+        }
+    }
+
+    /* Failed to copy temporary file */
+    fseek (oldstream, 0, SEEK_END);
+    fclose (newstream);
+    return;
+}
+
+
+static int KeyHandler (vlc_object_t *obj, char const *varname,
+                       vlc_value_t oldval, vlc_value_t newval, void *data)
+{
+    access_t *access = data;
+
+    (void)oldval;
+    (void)obj;
+
+    for (struct hotkey *key = access->p_libvlc->p_hotkeys;
+         key->psz_action != NULL; key++)
+    {
+        if (key->i_key == newval.i_int)
+        {
+            if (key->i_action == ACTIONID_DUMP)
+                Trigger ((access_t *)data);
+            break;
+        }
+    }
+
+    return VLC_SUCCESS;
+}