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some refactoring

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This commit is contained in:
Gregory 2019-07-13 15:10:26 +03:00
parent de74e299cc
commit dd68ed6846
1 changed files with 160 additions and 85 deletions
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245
src/main.c
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@ -1,3 +1,15 @@
/* ************************************************************************** */
/* */
/* ::: :::::::: */
/* main.c :+: :+: :+: */
/* +:+ +:+ +:+ */
/* By: gtertysh <marvin@42.fr> +#+ +:+ +#+ */
/* +#+#+#+#+#+ +#+ */
/* Created: 2019/07/13 14:52:27 by gtertysh #+# #+# */
/* Updated: 2019/07/13 14:52:29 by gtertysh ### ########.fr */
/* */
/* ************************************************************************** */
#include "libft.h" #include "libft.h"
#include <fcntl.h> #include <fcntl.h>
#include <sys/stat.h> #include <sys/stat.h>
@ -5,7 +17,6 @@
#include <mach-o/loader.h> #include <mach-o/loader.h>
#include <mach-o/nlist.h> #include <mach-o/nlist.h>
static void print_addr(void *addr) static void print_addr(void *addr)
{ {
size_t i; size_t i;
@ -25,106 +36,170 @@ static void print_addr(void *addr)
} }
} }
int main(int argc, char **argv) void open_file(const char *filename, int *fd, char **file)
{ {
if (argc != 2) struct stat stat_buff;
{
ft_putstr("usage\n"); *fd = open(filename, O_RDONLY);
return (1); if (*fd == -1)
}
int fd = open(argv[1], O_RDONLY);
if (fd == -1)
{ {
ft_putstr("can't open file\n"); ft_putstr("can't open file\n");
return (1); exit(1);
} }
struct stat stat_buff; stat(filename, &stat_buff);
stat(argv[1], &stat_buff);
if (!S_ISREG(stat_buff.st_mode)) if (!S_ISREG(stat_buff.st_mode))
{ {
ft_putstr("not a regular file\n"); ft_putstr("not a regular file\n");
return (1); close(*fd);
exit(1);
} }
char *file; *file = NULL;
file = malloc(stat_buff.st_size); *file = malloc(stat_buff.st_size);
read(fd, file, stat_buff.st_size); if (!*file)
uint32_t magic = *(uint32_t *)file;
if (magic != MH_MAGIC && magic != MH_MAGIC_64)
{ {
ft_putstr("not a mach-o file\n"); ft_putstr("can't allocate memory\n");
return (1); close(*fd);
exit(1);
} }
read(*fd, *file, stat_buff.st_size);
}
if (magic == MH_MAGIC) void close_file(int fd, char *file)
ft_putstr("32 bit mach-o file\n"); {
close(fd);
free(file);
}
void handle_64(char *file)
{
struct mach_header_64 *hdr;
struct load_command *load_cmd;
struct symtab_command *symtab_cmd;
struct segment_command_64 *segment_cmd;
if (magic == MH_MAGIC_64) hdr = (struct mach_header_64 *)file;
ft_putstr("64 bit mach-o file\n");
ft_putstr("# of cmds: ");
ft_putnbr(hdr->ncmds);
ft_putstr("\n");
ft_putstr("total cmds memory: ");
ft_putnbr(hdr->sizeofcmds);
ft_putstr("\n");
uint32_t load_cmd_offset = sizeof(struct mach_header_64);
uint32_t i = 0;
while (i < hdr->ncmds)
{ {
struct mach_header_64 *hdr = (struct mach_header_64 *)file; load_cmd = (struct load_command *)(file + load_cmd_offset);
// ft_putstr("64 bit mach-o file\n"); if (load_cmd->cmd == LC_SEGMENT_64)
// ft_putstr("# of cmds: ");
// ft_putnbr(hdr->ncmds);
// ft_putstr("\n");
// ft_putstr("total cmds memory: ");
// ft_putnbr(hdr->sizeofcmds);
// ft_putstr("\n");
struct load_command *load_cmd;
struct symtab_command *symtab_cmd;
uint32_t load_cmd_offset = sizeof(struct mach_header_64);
uint32_t i = 0;
while (i < hdr->ncmds)
{ {
load_cmd = (struct load_command *)(file + load_cmd_offset); segment_cmd = (struct segment_command_64 *)load_cmd;
if (load_cmd->cmd == LC_SYMTAB) ft_putnbr(i);
{ ft_putchar(' ');
symtab_cmd = (struct symtab_command *)load_cmd; ft_putnbr(segment_cmd->nsects);
// ft_putstr("found symbol table load command\n"); ft_putchar(' ');
// ft_putstr("# of symbols: "); ft_putstr(segment_cmd->segname);
// ft_putnbr(symtab_cmd->nsyms); ft_putchar('\n');
// ft_putstr("\n");
uint32_t j = 0;
struct nlist_64 *symbol_table = (struct nlist_64 *)
(file + symtab_cmd->symoff);
struct nlist_64 symbol;
char *str_table = file + symtab_cmd->stroff;
while(j < symtab_cmd->nsyms)
{
symbol = symbol_table[j];
int type = symbol.n_type & N_TYPE;
int external = symbol.n_type & N_EXT;
int debug = (symbol.n_type & N_STAB) != 0;
int offset = external ? 0 : 32;
char *name = str_table + symbol.n_un.n_strx;
if (debug)
{
j++;
continue;
}
if (symbol.n_value)
print_addr((void *)symbol.n_value);
else
ft_putstr(" ");
ft_putchar(' ');
if (type == N_UNDF)
ft_putchar('U' + offset);
if (type == N_ABS)
ft_putchar('A' + offset);
if (type == N_SECT)
// lookup in which section symbol is located
ft_putchar('T' + offset);
ft_putchar(' ');
ft_putstr(name);
ft_putstr("\n");
j++;
}
}
load_cmd_offset += load_cmd->cmdsize; load_cmd_offset += load_cmd->cmdsize;
i++; i++;
continue;
} }
if (load_cmd->cmd == LC_SYMTAB)
{
symtab_cmd = (struct symtab_command *)load_cmd;
ft_putstr("found symbol table load command\n");
ft_putstr("# of symbols: ");
ft_putnbr(symtab_cmd->nsyms);
ft_putstr("\n");
uint32_t j = 0;
struct nlist_64 *symbol_table = (struct nlist_64 *)
(file + symtab_cmd->symoff);
struct nlist_64 symbol;
char *str_table = file + symtab_cmd->stroff;
while(j < symtab_cmd->nsyms)
{
symbol = symbol_table[j];
int type = symbol.n_type & N_TYPE;
int external = symbol.n_type & N_EXT;
int debug = (symbol.n_type & N_STAB) != 0;
int offset = external ? 0 : 32;
char *name = str_table + symbol.n_un.n_strx;
if (debug)
{
j++;
continue;
}
// some shit herustic should be used
// to determine to print address or not
if (symbol.n_value)
print_addr((void *)symbol.n_value);
else
ft_putstr(" ");
ft_putchar(' ');
if (type == N_UNDF)
ft_putchar('U' + offset);
if (type == N_ABS)
ft_putchar('A' + offset);
if (type == N_SECT)
{
// lookup in which section symbol is located
ft_putchar('T' + offset);
ft_putchar(' ');
ft_putnbr(symbol.n_sect);
}
ft_putchar(' ');
ft_putstr(name);
ft_putstr("\n");
j++;
}
}
load_cmd_offset += load_cmd->cmdsize;
i++;
} }
} }
void handle_32(char *file)
{
(void)file;
ft_putstr("TODO\n");
}
void hanldle_file(const char *filename)
{
char *file;
int fd;
open_file(filename, &fd, &file);
uint32_t magic;
magic = *(uint32_t *)file;
if (magic == MH_MAGIC_64)
handle_64(file);
else if (magic == MH_MAGIC)
handle_64(file);
else if (magic == MH_CIGAM || magic == MH_CIGAM_64)
ft_putstr("do not support big endian binaries.");
else
ft_putstr("invalid magic number.");
close_file(fd, file);
}
int main(int argc, char **argv)
{
int i;
if (argc == 1)
hanldle_file("a.out");
else
{
i = 1;
while (i < argc)
hanldle_file(argv[i++]);
}
return (0);
}