You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
exercise_2/colmap-build/FreeImage/Examples/Generic/FIIO_Mem.cpp

147 lines
3.6 KiB

/*--------------------------------------------------------------------------*\
|| fiio_mem.cpp by Ryan Rubley <ryan@lostreality.org> ||
|| ||
|| (v1.02) 4-28-2004 ||
|| FreeImageIO to memory ||
|| ||
\*--------------------------------------------------------------------------*/
#include <string.h>
#include <stdlib.h>
#include "fiio_mem.h"
#ifdef __cplusplus
extern "C" {
#endif
FIBITMAP *
FreeImage_LoadFromMem(FREE_IMAGE_FORMAT fif, fiio_mem_handle *handle, int flags) {
FreeImageIO io;
SetMemIO(&io);
if (handle && handle->data) {
handle->curpos = 0;
return FreeImage_LoadFromHandle(fif, &io, (fi_handle)handle, flags);
}
return NULL;
}
BOOL
FreeImage_SaveToMem(FREE_IMAGE_FORMAT fif, FIBITMAP *dib, fiio_mem_handle *handle, int flags) {
FreeImageIO io;
SetMemIO(&io);
if (handle) {
handle->filelen = 0;
handle->curpos = 0;
return FreeImage_SaveToHandle(fif, dib, &io, (fi_handle)handle, flags);
}
return FALSE;
}
// ----------------------------------------------------------
void
SetMemIO(FreeImageIO *io) {
io->read_proc = fiio_mem_ReadProc;
io->seek_proc = fiio_mem_SeekProc;
io->tell_proc = fiio_mem_TellProc;
io->write_proc = fiio_mem_WriteProc;
}
// ----------------------------------------------------------
#define FIIOMEM(member) (((fiio_mem_handle *)handle)->member)
unsigned
fiio_mem_ReadProc(void *buffer, unsigned size, unsigned count, fi_handle handle) {
unsigned x;
for( x=0; x<count; x++ ) {
//if there isnt size bytes left to read, set pos to eof and return a short count
if( FIIOMEM(filelen)-FIIOMEM(curpos) < (long)size ) {
FIIOMEM(curpos) = FIIOMEM(filelen);
break;
}
//copy size bytes count times
memcpy( buffer, (char *)FIIOMEM(data) + FIIOMEM(curpos), size );
FIIOMEM(curpos) += size;
buffer = (char *)buffer + size;
}
return x;
}
unsigned
fiio_mem_WriteProc(void *buffer, unsigned size, unsigned count, fi_handle handle) {
void *newdata;
long newdatalen;
//double the data block size if we need to
while( FIIOMEM(curpos)+(long)(size*count) >= FIIOMEM(datalen) ) {
//if we are at or above 1G, we cant double without going negative
if( FIIOMEM(datalen) & 0x40000000 ) {
//max 2G
if( FIIOMEM(datalen) == 0x7FFFFFFF ) {
return 0;
}
newdatalen = 0x7FFFFFFF;
} else if( FIIOMEM(datalen) == 0 ) {
//default to 4K if nothing yet
newdatalen = 4096;
} else {
//double size
newdatalen = FIIOMEM(datalen) << 1;
}
newdata = realloc( FIIOMEM(data), newdatalen );
if( !newdata ) {
return 0;
}
FIIOMEM(data) = newdata;
FIIOMEM(datalen) = newdatalen;
}
memcpy( (char *)FIIOMEM(data) + FIIOMEM(curpos), buffer, size*count );
FIIOMEM(curpos) += size*count;
if( FIIOMEM(curpos) > FIIOMEM(filelen) ) {
FIIOMEM(filelen) = FIIOMEM(curpos);
}
return count;
}
int
fiio_mem_SeekProc(fi_handle handle, long offset, int origin) {
switch(origin) { //0 to filelen-1 are 'inside' the file
default:
case SEEK_SET: //can fseek() to 0-7FFFFFFF always
if( offset >= 0 ) {
FIIOMEM(curpos) = offset;
return 0;
}
break;
case SEEK_CUR:
if( FIIOMEM(curpos)+offset >= 0 ) {
FIIOMEM(curpos) += offset;
return 0;
}
break;
case SEEK_END:
if( FIIOMEM(filelen)+offset >= 0 ) {
FIIOMEM(curpos) = FIIOMEM(filelen)+offset;
return 0;
}
break;
}
return -1;
}
long
fiio_mem_TellProc(fi_handle handle) {
return FIIOMEM(curpos);
}
#ifdef __cplusplus
}
#endif