elf_loader_stdio.c

/*
# _____     ___ ____     ___ ____
#  ____|   |    ____|   |        | |____|
# |     ___|   |____ ___|    ____| |    \    PS2DEV Open Source Project.
#-----------------------------------------------------------------------
# Copyright ps2dev - http://www.ps2dev.org
# Licenced under Academic Free License version 2.0
# Review ps2sdk README & LICENSE files for further details.
*/
 
#include "elf_loader_common.h"
 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
typedef struct elf_loader_reader_info_stdio_
{
    FILE *m_fp;
    elf_loader_reader_info_t m_reader_info;
    elf_loader_reader_info_stdio_resultbuf_t m_resultbuf;
} elf_loader_reader_info_stdio_t;
 
static void *elf_loader_reader_read_elf_file_stdlib_allocation_callback(
    void *userdata, void *pointer, ptrdiff_t old_size, ptrdiff_t new_size)
{
    void *new_ptr;
    (void)userdata;
    (void)old_size;
 
    if ( !new_size )
    {
        free(pointer);
        return NULL;
    }
    new_ptr = realloc(pointer, new_size);
    if ( !new_ptr )
    {
        free(pointer);
    }
    return new_ptr;
}
 
static int elf_loader_reader_read_elf_file_stdio_read_callback(
    void *userdata, elf_loader_reader_stage_t stage, const elf_loader_reader_segment_info_t *segm_info, size_t segm_count)
{
    elf_loader_reader_info_stdio_t *procinfo;
    size_t i;
 
    procinfo = (elf_loader_reader_info_stdio_t *)userdata;
    if ( !procinfo->m_fp )
        return 0;
    for ( i = 0; i < segm_count; i += 1 )
    {
        if ( fseek(procinfo->m_fp, segm_info[i].m_segment_offset, SEEK_SET) )
        {
            return 0;
        }
        if ( ftell(procinfo->m_fp) != segm_info[i].m_segment_offset )
        {
            return 0;
        }
        if ( fread(segm_info[i].m_segment_addr, segm_info[i].m_segment_size, 1, procinfo->m_fp) != 1 )
        {
            return 0;
        }
    }
    return 1;
}
 
static void
elf_loader_reader_read_elf_file_stdio_result_callback(void *userdata, void *pointer, ptrdiff_t pointer_size, int errval)
{
    elf_loader_reader_info_stdio_t *procinfo;
 
    procinfo = (elf_loader_reader_info_stdio_t *)userdata;
    procinfo->m_resultbuf.m_buf = pointer;
    procinfo->m_resultbuf.m_bufsize = pointer_size;
    procinfo->m_resultbuf.m_result = errval;
}
 
int elf_loader_reader_read_elf_file_stdio(
    elf_loader_reader_info_stdio_resultbuf_t *resultbuf, const char *filename, const char *flags)
{
    elf_loader_reader_info_stdio_t procinfo;
 
    procinfo.m_reader_info.m_userdata = &procinfo;
    procinfo.m_reader_info.m_alloc_callback = elf_loader_reader_read_elf_file_stdlib_allocation_callback;
    procinfo.m_reader_info.m_read_callback = elf_loader_reader_read_elf_file_stdio_read_callback;
    procinfo.m_reader_info.m_result_callback = elf_loader_reader_read_elf_file_stdio_result_callback;
    procinfo.m_fp = fopen(filename, flags);
    if ( !procinfo.m_fp )
        return -30;
    elf_loader_reader_read_elf_file(&procinfo.m_reader_info);
    if ( procinfo.m_fp )
    {
        fclose(procinfo.m_fp);
        procinfo.m_fp = NULL;
    }
    if ( resultbuf )
        memcpy(resultbuf, &procinfo.m_resultbuf, sizeof(elf_loader_reader_info_stdio_resultbuf_t));
    return procinfo.m_resultbuf.m_result;
}