some basic session management

1 files changed, 227 insertions, 0 deletions

diff --git a/session.c b/session.c
new file mode 100644
index 00000000..ca42dfdf
--- /dev/null
+++ b/session.c
@@ -0,0 +1,227 @@
+/*
+    DeaDBeeF - ultimate music player for GNU/Linux systems with X11
+    Copyright (C) 2009  Alexey Yakovenko
+
+    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 <stdio.h>
+#include <string.h>
+#include <stdint.h>
+#include "session.h"
+#include "common.h"
+
+char session_dir[2048];
+float session_volume;
+int session_win_attrs[5] = { 40, 40, 500, 300, 0 };
+static uint8_t sessfile_magic[] = { 0xdb, 0xef, 0x5e, 0x55 }; // dbefsess in hexspeak
+
+static int
+write_i16_be (uint16_t val, FILE *fp) {
+    uint8_t b;
+    b = (uint8_t)(val&0xff);
+    if (fwrite (&b, 1, 1, fp) != 1) {
+        return 0;
+    }
+    b = (uint8_t)((val&0xff00)>>8);
+    if (fwrite (&b, 1, 1, fp) != 1) {
+        return 1;
+    }
+    return 2;
+}
+
+static int
+write_i32_be (uint32_t val, FILE *fp) {
+    uint8_t b;
+    b = (uint8_t)(val&0xff);
+    if (fwrite (&b, 1, 1, fp) != 1) {
+        return 0;
+    }
+    b = (uint8_t)((val&0xff00)>>8);
+    if (fwrite (&b, 1, 1, fp) != 1) {
+        return 1;
+    }
+    b = (uint8_t)((val&0xff0000)>>16);
+    if (fwrite (&b, 1, 1, fp) != 1) {
+        return 2;
+    }
+    b = (uint8_t)((val&0xff000000)>>24);
+    if (fwrite (&b, 1, 1, fp) != 1) {
+        return 3;
+    }
+    return 4;
+}
+
+static int
+read_i16_be (uint16_t *pval, FILE *fp) {
+    uint16_t val = 0;
+    uint8_t b;
+    if (fread (&b, 1, 1, fp) != 1) {
+        return 0;
+    }
+    val |= (uint16_t)b;
+    if (fread (&b, 1, 1, fp) != 1) {
+        return 1;
+    }
+    val |= (((uint16_t)b) << 8);
+    *pval = val;
+    return 2;
+}
+
+static int
+read_i32_be (uint32_t *pval, FILE *fp) {
+    uint32_t val = 0;
+    uint8_t b;
+    if (fread (&b, 1, 1, fp) != 1) {
+        return 0;
+    }
+    val |= (uint32_t)b;
+    if (fread (&b, 1, 1, fp) != 1) {
+        return 1;
+    }
+    val |= (((uint32_t)b) << 8);
+    if (fread (&b, 1, 1, fp) != 1) {
+        return 2;
+    }
+    val |= (((uint32_t)b) << 16);
+    if (fread (&b, 1, 1, fp) != 1) {
+        return 3;
+    }
+    val |= (((uint32_t)b) << 24);
+    *pval = val;
+    return 4;
+}
+
+void
+session_reset (void) {
+    session_volume = 0;
+    session_dir[0] = 0;
+    session_win_attrs[0] = 40;
+    session_win_attrs[1] = 40;
+    session_win_attrs[2] = 500;
+    session_win_attrs[3] = 300;
+    session_win_attrs[4] = 0;
+}
+
+int
+session_save (const char *fname) {
+    FILE *fp = fopen (fname, "w+b");
+    if (!fp) {
+        fprintf (stderr, "failed to save session, file %s could not be opened\n");
+        return -1;
+    }
+    // magic
+    if (fwrite (sessfile_magic, 1, 4, fp) != 4) {
+        goto session_save_fail;
+    }
+    uint8_t version = 1;
+    if (fwrite (&version, 1, 1, fp) != 1) {
+        goto session_save_fail;
+    }
+    uint16_t l = strlen (session_dir);
+    if (write_i16_be (l, fp) != 2) {
+        goto session_save_fail;
+    }
+    if (fwrite (session_dir, 1, l, fp) != l) {
+        goto session_save_fail;
+    }
+    if (write_i32_be (*((uint32_t*)&session_volume), fp) != 4) {
+        goto session_save_fail;
+    }
+    for (int k = 0; k < 5; k++) {
+        if (write_i32_be (session_win_attrs[k], fp) != 4) {
+            goto session_save_fail;
+        }
+    }
+    fclose (fp);
+    return 0;
+session_save_fail:
+    fprintf (stderr, "failed to save session, seems to be a disk error\n");
+    fclose (fp);
+    return -1;
+}
+
+int
+session_load (const char *fname) {
+    FILE *fp = fopen (fname, "r+b");
+    if (!fp) {
+        return -1;
+    }
+    // magic
+    uint8_t magic[4];
+    if (fread (magic, 1, 4, fp) != 4) {
+        goto session_load_fail;
+    }
+    if (memcmp (magic, sessfile_magic, 4)) {
+        goto session_load_fail;
+    }
+    uint8_t version;
+    if (fread (&version, 1, 1, fp) != 1) {
+        goto session_load_fail;
+    }
+    if (version != 1) {
+        goto session_load_fail;
+    }
+    uint16_t l;
+    if (read_i16_be (&l, fp) != 2) {
+        goto session_load_fail;
+    }
+    if (l >= 2048) {
+        goto session_load_fail;
+    }
+    if (fread (session_dir, 1, l, fp) != l) {
+        goto session_load_fail;
+    }
+    session_dir[l] = 0;
+    if (read_i32_be ((uint32_t*)&session_volume, fp) != 4) {
+        goto session_load_fail;
+    }
+    for (int k = 0; k < 5; k++) {
+        if (read_i32_be (&session_win_attrs[k], fp) != 4) {
+            goto session_load_fail;
+        }
+    }
+//    printf ("dir: %s\n", session_dir);
+//    printf ("volume: %f\n", session_volume);
+//    printf ("win: %d %d %d %d %d\n", session_win_attrs[0], session_win_attrs[1], session_win_attrs[2], session_win_attrs[3], session_win_attrs[4]);
+    fclose (fp);
+    return 0;
+session_load_fail:
+    fprintf (stderr, "failed to load session, session file is corrupt\n");
+    fclose (fp);
+    session_reset ();
+    return -1;
+}
+
+void
+session_set_directory (const char *path) {
+    strncpy (session_dir, path, 2048);
+}
+
+void
+session_set_volume (float vol) {
+    printf ("volume: %f\n", vol);
+    session_volume = vol;
+}
+
+const char *
+session_get_directory (void) {
+    return session_dir;
+}
+
+float
+session_get_volume (void) {
+    return session_volume;
+}
+