quake: cache files in memory to eliminate skips
This caches large files (arbitrarily defined as >1MB) in memory, which
reduces the delay when a new model or sound is needed.
Change-Id: I0f96449555a32f05d771fe900c10eaf21ecbb4f6
diff --git a/apps/plugins/sdl/progs/quake/sys_sdl.c b/apps/plugins/sdl/progs/quake/sys_sdl.c
index 3cc3122..44411bd 100644
--- a/apps/plugins/sdl/progs/quake/sys_sdl.c
+++ b/apps/plugins/sdl/progs/quake/sys_sdl.c
@@ -116,16 +116,25 @@
*/
#define MAX_HANDLES 10
-static FILE *sys_handles[MAX_HANDLES];
+//static FILE *sys_handles[MAX_HANDLES];
+
+/* a file fully or partially cached in memory */
+/* We use the FILE handle to track the current position */
+static struct memfile {
+ FILE *f; /* NULL: unused slot */
+ char *buf;
+ size_t resident_len; /* bytes 0-(resident_len-1) are in memory */
+ size_t full_len;
+} sys_handles[MAX_HANDLES];
void Sys_Shutdown(void)
{
for(int i = 0; i < MAX_HANDLES; i++)
{
- FILE *f = sys_handles[i];
+ FILE *f = sys_handles[i].f;
if(f)
fclose(f);
- sys_handles[i] = NULL;
+ sys_handles[i].f = NULL;
}
}
@@ -134,7 +143,7 @@
int i;
for (i=1 ; i<MAX_HANDLES ; i++)
- if (!sys_handles[i])
+ if (!sys_handles[i].f)
return i;
Sys_Error ("out of handles");
return -1;
@@ -158,26 +167,60 @@
return end;
}
+#define CACHE_THRESHOLD (1024*1024)
+
+/* really rough guesses */
+#if MEMORYSIZE >= 64
+#define MAX_CACHE (32*1024*1024)
+#elif MEMORYSIZE >= 32
+#define MAX_CACHE (20*1024*1024)
+#else
+#define MAX_CACHE 0
+#endif
+
+static int cache_left = MAX_CACHE;
+
int Sys_FileOpenRead (char *path, int *hndl)
{
- FILE *f;
- int i;
+ FILE *f;
+ int i;
- i = findhandle ();
+ i = findhandle ();
- f = fopen(path, "rb");
- if (!f)
- {
- *hndl = -1;
- return -1;
- }
- sys_handles[i] = f;
- *hndl = i;
+ f = fopen(path, "rb");
+ if (!f)
+ {
+ *hndl = -1;
+ return -1;
+ }
+ sys_handles[i].f = f;
+ *hndl = i;
- //rb->splashf(HZ*2, "Allocating handle %d to %s", i, path);
-
-
- return Qfilelength(f);
+ //rb->splashf(HZ*2, "Allocating handle %d to %s", i, path);
+
+ int len = sys_handles[i].full_len = Qfilelength(f);
+
+ /* cache in memory? */
+ if(len > CACHE_THRESHOLD && cache_left > 0)
+ {
+ /* cache all or part of it */
+ int cachelen = (cache_left > len) ? len : cache_left;
+
+ if((sys_handles[i].buf = malloc(cachelen)))
+ {
+ cache_left -= cachelen;
+
+ /* fill in cache */
+ printf("Please wait... caching %d KB of large file", cachelen / 1024);
+ if(fread(sys_handles[i].buf, 1, cachelen, f) == cachelen)
+ {
+ sys_handles[i].resident_len = cachelen;
+ fseek(f, 0, SEEK_SET);
+
+ printf("Success!");
+ }
+ }
+ }
}
int Sys_FileOpenWrite (char *path)
@@ -190,7 +233,7 @@
f = fopen(path, "wb");
if (!f)
Sys_Error ("Error opening %s: %s", path,strerror(errno));
- sys_handles[i] = f;
+ sys_handles[i].f = f;
return i;
}
@@ -199,15 +242,19 @@
{
if ( handle >= 0 ) {
//rb->splashf(HZ, "Close handle %d", handle);
- fclose (sys_handles[handle]);
- sys_handles[handle] = NULL;
+ fclose (sys_handles[handle].f);
+
+ cache_left += sys_handles[handle].resident_len;
+
+ // clear all fields so we can safely reuse
+ memset(sys_handles + handle, 0, sizeof(sys_handles[0]));
}
}
void Sys_FileSeek (int handle, int position)
{
if ( handle >= 0 ) {
- fseek (sys_handles[handle], position, SEEK_SET);
+ fseek (sys_handles[handle].f, position, SEEK_SET);
}
}
@@ -218,20 +265,38 @@
size = 0;
if ( handle >= 0 ) {
- data = dst;
- while ( count > 0 ) {
- done = fread (data, 1, count, sys_handles[handle]);
- if ( done == 0 ) {
- break;
- }
- else if(done < 0)
- {
- Sys_Error("stream error %d, file is %d = %d", done, handle, sys_handles[handle]);
- }
- data += done;
- count -= done;
- size += done;
- }
+ FILE *f = sys_handles[handle].f;
+
+ data = dst;
+
+ /* partially or fully in memory */
+ int pos = ftell(f);
+ if(pos < sys_handles[handle].resident_len)
+ {
+ int memleft = sys_handles[handle].resident_len - pos;
+ int memlen = MIN(count, memleft);
+
+ memcpy(data, sys_handles[handle].buf + pos, memlen);
+ data += memlen;
+ count -= memlen;
+ size += memlen;
+
+ fseek(f, memlen, SEEK_CUR);
+ }
+
+ while ( count > 0 ) {
+ done = fread (data, 1, count, sys_handles[handle].f);
+ if ( done == 0 ) {
+ break;
+ }
+ else if(done < 0)
+ {
+ Sys_Error("stream error %d, file is %d = %d", done, handle, sys_handles[handle]);
+ }
+ data += done;
+ count -= done;
+ size += done;
+ }
}
return size;
@@ -246,7 +311,7 @@
if ( handle >= 0 ) {
data = src;
while ( count > 0 ) {
- done = fread (data, 1, count, sys_handles[handle]);
+ done = fread (data, 1, count, sys_handles[handle].f);
if ( done == 0 ) {
break;
}