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#include <inttypes.h>
#include <stdint.h>
#include <unistd.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <err.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <tools/le_byteshift.h>
#include <linux/elf.h>
#include <linux/types.h>
const char *outfilename;
/* Symbols that we need in vdso2c. */
enum {
sym_vvar_page,
sym_hpet_page,
sym_end_mapping,
sym_VDSO_FAKE_SECTION_TABLE_START,
sym_VDSO_FAKE_SECTION_TABLE_END,
};
const int special_pages[] = {
sym_vvar_page,
sym_hpet_page,
};
struct vdso_sym {
const char *name;
bool export;
};
struct vdso_sym required_syms[] = {
[sym_vvar_page] = {"vvar_page", true},
[sym_hpet_page] = {"hpet_page", true},
[sym_end_mapping] = {"end_mapping", true},
[sym_VDSO_FAKE_SECTION_TABLE_START] = {
"VDSO_FAKE_SECTION_TABLE_START", false
},
[sym_VDSO_FAKE_SECTION_TABLE_END] = {
"VDSO_FAKE_SECTION_TABLE_END", false
},
{"VDSO32_NOTE_MASK", true},
{"VDSO32_SYSENTER_RETURN", true},
{"__kernel_vsyscall", true},
{"__kernel_sigreturn", true},
{"__kernel_rt_sigreturn", true},
};
__attribute__((format(printf, 1, 2))) __attribute__((noreturn))
static void fail(const char *format, ...)
{
va_list ap;
va_start(ap, format);
fprintf(stderr, "Error: ");
vfprintf(stderr, format, ap);
unlink(outfilename);
exit(1);
va_end(ap);
}
/*
* Evil macros for little-endian reads and writes
*/
#define GLE(x, bits, ifnot) \
__builtin_choose_expr( \
(sizeof(*(x)) == bits/8), \
(__typeof__(*(x)))get_unaligned_le##bits(x), ifnot)
extern void bad_get_le(void);
#define LAST_GLE(x) \
__builtin_choose_expr(sizeof(*(x)) == 1, *(x), bad_get_le())
#define GET_LE(x) \
GLE(x, 64, GLE(x, 32, GLE(x, 16, LAST_GLE(x))))
#define PLE(x, val, bits, ifnot) \
__builtin_choose_expr( \
(sizeof(*(x)) == bits/8), \
put_unaligned_le##bits((val), (x)), ifnot)
extern void bad_put_le(void);
#define LAST_PLE(x, val) \
__builtin_choose_expr(sizeof(*(x)) == 1, *(x) = (val), bad_put_le())
#define PUT_LE(x, val) \
PLE(x, val, 64, PLE(x, val, 32, PLE(x, val, 16, LAST_PLE(x, val))))
#define NSYMS (sizeof(required_syms) / sizeof(required_syms[0]))
#define BITSFUNC3(name, bits) name##bits
#define BITSFUNC2(name, bits) BITSFUNC3(name, bits)
#define BITSFUNC(name) BITSFUNC2(name, ELF_BITS)
#define ELF_BITS_XFORM2(bits, x) Elf##bits##_##x
#define ELF_BITS_XFORM(bits, x) ELF_BITS_XFORM2(bits, x)
#define ELF(x) ELF_BITS_XFORM(ELF_BITS, x)
#define ELF_BITS 64
#include "vdso2c.h"
#undef ELF_BITS
#define ELF_BITS 32
#include "vdso2c.h"
#undef ELF_BITS
static void go(void *addr, size_t len, FILE *outfile, const char *name)
{
Elf64_Ehdr *hdr = (Elf64_Ehdr *)addr;
if (hdr->e_ident[EI_CLASS] == ELFCLASS64) {
go64(addr, len, outfile, name);
} else if (hdr->e_ident[EI_CLASS] == ELFCLASS32) {
go32(addr, len, outfile, name);
} else {
fail("unknown ELF class\n");
}
}
int main(int argc, char **argv)
{
int fd;
off_t len;
void *addr;
FILE *outfile;
char *name, *tmp;
int namelen;
if (argc != 3) {
printf("Usage: vdso2c INPUT OUTPUT\n");
return 1;
}
/*
* Figure out the struct name. If we're writing to a .so file,
* generate raw output insted.
*/
name = strdup(argv[2]);
namelen = strlen(name);
if (namelen >= 3 && !strcmp(name + namelen - 3, ".so")) {
name = NULL;
} else {
tmp = strrchr(name, '/');
if (tmp)
name = tmp + 1;
tmp = strchr(name, '.');
if (tmp)
*tmp = '\0';
for (tmp = name; *tmp; tmp++)
if (*tmp == '-')
*tmp = '_';
}
fd = open(argv[1], O_RDONLY);
if (fd == -1)
err(1, "%s", argv[1]);
len = lseek(fd, 0, SEEK_END);
if (len == (off_t)-1)
err(1, "lseek");
addr = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
if (addr == MAP_FAILED)
err(1, "mmap");
outfilename = argv[2];
outfile = fopen(outfilename, "w");
if (!outfile)
err(1, "%s", argv[2]);
go(addr, (size_t)len, outfile, name);
munmap(addr, len);
fclose(outfile);
return 0;
}
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