Files
player/Project/Src/MyApp/elf.c

494 lines
9.2 KiB
C
Raw Normal View History

2025-06-27 00:32:57 +08:00
#include <stdio.h>
/**
* hello.c
*/
#include <stdlib.h>
#include <string.h>
#include <elf.h>
#include <errno.h>
#include "rtthread.h"
//#define FILE ft_file_struct
//#define fclose ft_if_fclose
//#define fopen ft_if_fopen
//#define fread ft_if_fread
//#define fseek ft_if_fseek
//#define ftell ft_if_ftell
static appm_list_struct g_app_list={0};
//找到一个空的app结构体
static app_struct *appm_new(void)
{
if(g_app_list.used<APPM_LIST_MAXLEN)
{
for(int i=0;i<APPM_LIST_MAXLEN;i++)
{
app_struct *ptr=&g_app_list.app[i];
if(ptr->exe_addr==0)
{
g_app_list.used++;
return ptr;
}
}
}
return 0;
}
static int appm_delete (app_struct *app)
{
if(app==0) return -1;
for(int i=0;i<APPM_LIST_MAXLEN;i++)
{
app_struct *ptr=&g_app_list.app[i];
if(ptr==app)
{
memset(ptr,0,sizeof(app_struct));
g_app_list.used--;
return 0;
}
}
return -1;
}
app_struct * appm_find (char *name)
{
for(int i=0;i<APPM_LIST_MAXLEN;i++)
{
app_struct *ptr=&g_app_list.app[i];
if(strcmp(ptr->app_info->name,name)==0)
{
return ptr;
}
}
return 0;
}
app_struct *appm_get(int index)
{
if(index>=0&&index<APPM_LIST_MAXLEN)
{
if(g_app_list.app[index].exe_addr)
return &g_app_list.app[index];
else
return 0;
}
return 0;
}
// 获取当前正在运行的app数目
int appm_get_running_num(void)
{
int ret=0;
for(int i=0;i<APPM_LIST_MAXLEN;i++)
{
app_struct *ptr=&g_app_list.app[i];
if(ptr->run_state) ret++;
}
return ret;
}
/**elf 文件头和section表解析和检查***/
static int check_elf_head(app_struct * app )
{
if(app==0) return -1;
FILE *file_elf = app->file;
if(file_elf==0) return -1;
int i = 0;
int MagNum = 0;
unsigned long file_size = 0;
int sechnum = 0;
uint32_t symsize = 0;
uint32_t symoff = 0;
uint32_t nSyms = 0,kk=0;
Elf32_Ehdr *Elf_header = malloc(sizeof(Elf32_Ehdr));
/*文件大小*/
fseek(file_elf,0,SEEK_END);
file_size = ftell(file_elf);
fseek(file_elf,0,SEEK_SET);
printf("file total size is:%ld bytes\r\n",file_size);
fread(Elf_header,sizeof(Elf32_Ehdr),1,file_elf);
/**确认是否为elf格式**/
if((Elf_header->e_ident[EI_MAG0] == ELFMAG0) && (Elf_header->e_ident[EI_MAG1] == ELFMAG1) \
&& (Elf_header->e_ident[EI_MAG2] == ELFMAG2) && (Elf_header->e_ident[EI_MAG3] == ELFMAG3))
{
printf("This is ELF file!\r\n");
}
else
{
printf("NOT ELF file!\r\n");
free(Elf_header);
return -1;
}
free(Elf_header);
return 0;
}
/* 加载elf文件segment 到内存中 */
static int load_elf_2_mem(app_struct * app)
{
if(app==0) return -1;
Elf32_Phdr *phdr_head = NULL;
Elf32_Ehdr *Elf_header = NULL;
FILE *file1 = app->file;
uint32_t rb;
Elf_header = (Elf32_Ehdr *)malloc(sizeof(Elf32_Ehdr));
memset(Elf_header,0,sizeof(Elf32_Ehdr));
fseek(file1,0,SEEK_SET);
rb = fread(Elf_header, sizeof(Elf32_Ehdr), 1, file1);
/* 这里 Elf_header->e_phentsize 应该是== sizeof(Elf32_Phdr)*/
phdr_head=malloc(Elf_header->e_phentsize *Elf_header->e_phnum);
fseek(file1,Elf_header->e_phoff,SEEK_SET);
fread(phdr_head,Elf_header->e_phentsize,Elf_header->e_phnum,file1);
//Elf_header->e_phnum一般等于1
for(int i=0;i< Elf_header->e_phnum; i++)
{
//是程序节
//Keil编译的时候程序分为RORWZI3个节但是从运行时角度看来这3个节合并为一个段了
if(phdr_head[i].p_type == PT_LOAD )
{
//内存
if(app->exe_addr==0)
{
app->exe_addr=malloc(phdr_head[i].p_memsz);
fseek( file1,phdr_head[i].p_offset,SEEK_SET);
if((rb = fread(app->exe_addr,1,phdr_head[i].p_filesz,file1)) != phdr_head[i].p_filesz)
{
printf("function:%s,line:%d, read p_vaddr err!\r\n",__FUNCTION__,__LINE__);
printf("read 返回值%d\r\n",rb);
printf("read(file,ProHead->p_vaddr,ProHead->p_filesz) != ProHead->p_filesz %x p_filesz %d\r\n",\
phdr_head[i].p_vaddr,phdr_head[i].p_filesz);
}
/**多余的空间写0做BSS段**/
if((phdr_head[i].p_filesz) < (phdr_head[i].p_memsz))
{
memset((uint8_t*)app->exe_addr+phdr_head[i].p_filesz,
0,
phdr_head[i].p_memsz - phdr_head[i].p_filesz);
}
//找到入口函数地址
app->main=(int (*)(void *))((int)app->exe_addr+Elf_header->e_entry);
//程序描述信息地址
app->app_info=(app_info_struct *)app->exe_addr;
printf("%s:exe_addr=0X%08X,size=%d\r\n",__func__,(uint32_t)app->exe_addr,phdr_head[i].p_memsz);
printf("%s:main()=0X%08X\r\n",__func__,(uint32_t)app->main);
printf("%s:name=%s\r\n",__func__,app->app_info->name);
break;
}
}
}
//这里求得RW区在程序映像中的偏移
Elf32_Shdr *sher_head=NULL;
sher_head=malloc(Elf_header->e_shentsize *Elf_header->e_shnum);
fseek(file1,Elf_header->e_shoff,SEEK_SET);
fread(sher_head,Elf_header->e_shentsize,Elf_header->e_shnum,file1);
for(int i=0;i<Elf_header->e_shnum;i++)
{
if((sher_head[i].sh_type==SHT_PROGBITS)&&(sher_head[i].sh_flags==(SHF_ALLOC|SHF_EXECINSTR)))
{
app->ro_size=sher_head[i].sh_size;
break;
}
}
free(sher_head);
free(Elf_header);
free(phdr_head);
return 0;
}
//关闭app文件
static void app_close(app_struct *app)
{
if(app==0) return;
if(app->file) fclose(app->file);
}
//打开app文件
static int app_open(app_struct *app,char *path)
{
if(app==0) return -1;
app->file=fopen(path,"rb");
if(app->file)
{
return 0;
}
else
return -1;
}
//从文件中获取app的名称
//name,用于保存文件名的数组长度必须不小于APP_INFO_NAME_MAXLEN
//返回正数成功0失败正数代表程序的类型
int app_get_name_from_file(char *path,char *name)
{
if(path==0) return 0;
if(name==0) return 0;
Elf32_Phdr *phdr_head = NULL;
Elf32_Ehdr *Elf_header = NULL;
FILE *file1 = fopen(path,"rb");
uint32_t rb;
if(file1==0) return 0;
Elf_header = (Elf32_Ehdr *)malloc(sizeof(Elf32_Ehdr));
memset(Elf_header,0,sizeof(Elf32_Ehdr));
fseek(file1,0,SEEK_SET);
rb = fread(Elf_header, sizeof(Elf32_Ehdr), 1, file1);
/* 这里 Elf_header->e_phentsize 应该是== sizeof(Elf32_Phdr)*/
phdr_head=malloc(Elf_header->e_phentsize *Elf_header->e_phnum);
fseek(file1,Elf_header->e_phoff,SEEK_SET);
fread(phdr_head,Elf_header->e_phentsize,Elf_header->e_phnum,file1);
//Elf_header->e_phnum一般等于1
for(int i=0;i< Elf_header->e_phnum; i++)
{
//是程序节
//Keil编译的时候程序分为RORWZI3个节但是从运行时角度看来这3个节合并为一个段了
if(phdr_head[i].p_type == PT_LOAD )
{
fseek( file1,phdr_head[i].p_offset,SEEK_SET);
if((rb = fread(name,1,APP_INFO_NAME_MAXLEN,file1)) == APP_INFO_NAME_MAXLEN)
{
int app_type=0;
fread(&app_type,1,sizeof(int),file1);
fclose(file1);
free(Elf_header);
free(phdr_head);
return app_type;
}
}
}
fclose(file1);
free(Elf_header);
free(phdr_head);
return 0;
}
//app退出运行 0,成功非0失败
int app_exit(app_struct *app)
{
if(app==0) return -1;
//如果app正在运行需要先退出app
if(app->run_state&&app->exit)
{
app->exit(0);
}
if(app->run_state==0)
{
//在app没有运行时才可以删除
if(app->exe_addr) free(app->exe_addr);
appm_delete(app);
return 0;
}
else
{
return -1;
}
}
//获取和保存r9寄存器
void *get_r9(void);
void set_r9(void *r9);
//抢占式调用app阻塞调用线程以运行app
static int app_run_seize(app_struct *app)
{
int ret=0;
app->r9=get_r9();
set_r9((void *)((int)app->exe_addr+app->ro_size));
if (app->main) app->main(app);
set_r9(app->r9);
app_exit(app);
return ret;
}
//调用app保留app镜像
static int app_run_hold(app_struct *app)
{
int ret=0;
if(app==0) return -1;
app->r9=get_r9();
set_r9((void *)((int)app->exe_addr+app->ro_size));
if (app->main) app->main(app);
set_r9(app->r9);
return ret;
}
static void run_thread_entry(void *t)
{
app_struct *app=t;
int ret=0;
app->r9=get_r9();
set_r9((void *)((int)app->exe_addr+app->ro_size));
if (app->main) app->main(app);
set_r9(app->r9);
app_exit(app);
}
//创建新线程以运行app
static int app_run_thread(app_struct *app)
{
int ret=0;
rt_thread_t rt=rt_thread_create(app->app_info->name,run_thread_entry,app,
app->app_info->stack_size,app->app_info->priority,20);
rt_thread_startup(rt);
ret=0;
return ret;
}
//运行app
int app_run(app_struct *app)
{
int ret=0;
if(app->app_info->exe_type==APP_TYPE_SEIZE)
{
ret=app_run_seize(app);
}
else if(app->app_info->exe_type==APP_TYPE_THREAD)
{
ret=app_run_thread(app);
}
else if(app->app_info->exe_type==APP_TYPE_HOLD)
{
ret=app_run_hold(app);
}
return ret;
}
int app_run_path(char *path)
{
int ret=0;
//如果程序已经存在于内存中,则直接调用
char name[APP_INFO_NAME_MAXLEN]={0};
if(app_get_name_from_file(path,name)!=0)
{
app_struct *app=appm_find(name);
if(app)
{
if(app->app_info->exe_type==APP_TYPE_HOLD)
{
ret=app_run_hold(app);
}
return ret;
}
}
app_struct *app=appm_new();
if((app_open(app,path)==0)&&(check_elf_head(app)==0)&&(load_elf_2_mem(app)==0))
{
app_close(app);
app_run(app);
}
else
{
appm_delete(app);
ret=-1;
}
return ret;
}