dvander@27: #include "memfile.h"
dvander@27: #include <string.h>
dvander@27: #include "osdefs.h"
dvander@27: 
dvander@27: memfile_t *memfile_creat(const char *name, size_t init)
dvander@27: {
dvander@27: 	memfile_t mf;
dvander@27: 	memfile_t *pmf;
dvander@27: 
dvander@27: 	mf.size = init;
dvander@27: 	mf.base = (char *)malloc(init);
dvander@27: 	mf.usedoffs = 0;
dvander@27: 	if (!mf.base)
dvander@27: 	{
dvander@27: 		return NULL;
dvander@27: 	}
dvander@27: 
dvander@27: 	mf.offs = 0;
dvander@27: 	mf._static = 0;
dvander@27: 
dvander@27: 	pmf = (memfile_t *)malloc(sizeof(memfile_t));
dvander@27: 	memcpy(pmf, &mf, sizeof(memfile_t));
dvander@27: 
dvander@27: 	pmf->name = strdup(name);
dvander@27: 
dvander@27: 	return pmf;
dvander@27: }
dvander@27: 
dvander@27: void memfile_destroy(memfile_t *mf)
dvander@27: {
dvander@31: 	if (!mf)
dvander@31: 	{
dvander@31: 		return;
dvander@31: 	}
dvander@31: 
dvander@27: 	if (!mf->_static)
dvander@27: 	{
dvander@27: 		free(mf->name);
dvander@27: 		free(mf->base);
dvander@27: 		free(mf);
dvander@27: 	}
dvander@27: }
dvander@27: 
dvander@27: void memfile_seek(memfile_t *mf, long seek)
dvander@27: {
dvander@27: 	mf->offs = seek;
dvander@27: }
dvander@27: 
dvander@27: long memfile_tell(memfile_t *mf)
dvander@27: {
dvander@27: 	return mf->offs;
dvander@27: }
dvander@27: 
dvander@27: size_t memfile_read(memfile_t *mf, void *buffer, size_t maxsize)
dvander@27: {
dvander@27: 	if (!maxsize || mf->offs >= mf->usedoffs)
dvander@27: 	{
dvander@27: 		return 0;
dvander@27: 	}
dvander@27: 
dvander@27: 	if (mf->usedoffs - mf->offs < (long)maxsize)
dvander@27: 	{
dvander@27: 		maxsize = mf->usedoffs - mf->offs;
dvander@27: 		if (!maxsize)
dvander@27: 		{
dvander@27: 			return 0;
dvander@27: 		}
dvander@27: 	}
dvander@27: 
dvander@27: 	memcpy(buffer, mf->base + mf->offs, maxsize);
dvander@27: 
dvander@27: 	mf->offs += maxsize;
dvander@27: 
dvander@27: 	return maxsize;
dvander@27: }
dvander@27: 
dvander@31: int memfile_write(memfile_t *mf, const void *buffer, size_t size)
dvander@27: {
dvander@27: 	if (mf->offs + size > mf->size)
dvander@27: 	{
dvander@27: 		size_t newsize = (mf->size + size) * 2;
dvander@27: 		if (mf->_static)
dvander@27: 		{
dvander@27: 			char *oldbase = mf->base;
dvander@27: 			mf->base = (char *)malloc(newsize);
dvander@27: 			if (!mf->base)
dvander@27: 			{
dvander@27: 				return 0;
dvander@27: 			}
dvander@27: 			memcpy(mf->base, oldbase, mf->size);
dvander@27: 		} else {
dvander@27: 			mf->base = (char *)realloc(mf->base, newsize);
dvander@27: 			if (!mf->base)
dvander@27: 			{
dvander@27: 				return 0;
dvander@27: 			}
dvander@27: 		}
dvander@27: 		mf->_static = 0;
dvander@27: 		mf->size = newsize;
dvander@27: 	}
dvander@27: 	memcpy(mf->base + mf->offs, buffer, size);
dvander@27: 	mf->offs += size;
dvander@27: 
dvander@27: 	if (mf->offs > mf->usedoffs)
dvander@27: 	{
dvander@27: 		mf->usedoffs = mf->offs;
dvander@27: 	}
dvander@27: 
dvander@27: 	return 1;
dvander@27: }
dvander@31: 
dvander@31: void memfile_reset(memfile_t *mf)
dvander@31: {
dvander@31: 	mf->usedoffs = 0;
dvander@31: 	mf->offs = 0;
dvander@31: }