1 // vim:shiftwidth=2:expandtab
10 #define CHECK_(val, fail_operator, expect, err_msg) \
11 if (val fail_operator expect) { \
12 fprintf(stderr, err_msg ", exiting (%d)\n", (int)(long)val); \
16 #define CHECK_EQ(val, expect, err_msg) \
17 CHECK_(val, !=, expect, err_msg)
19 #define CHECK_NE(val, expect, err_msg) \
20 CHECK_(val, ==, expect, err_msg)
22 #define HDR_CHECK_EQ(field, expect, err_msg) \
23 CHECK_(hdr.field, !=, expect, err_msg)
25 #define HDR_CHECK_NE(field, expect, err_msg) \
26 CHECK_(hdr.field, ==, expect, err_msg)
28 #define FAIL_PERROR(msg) { \
38 static int is_range_used(maps_range *maps, int map_cnt, unsigned long start, unsigned long end)
41 for (i = 0; i < map_cnt; i++) {
42 if (maps[i].end <= start)
44 if (end <= maps[i].start)
53 extern char **environ;
55 int main(int argc, char *argv[])
57 void *lowest_segment = (void *)-1;
67 fprintf(stderr, "usage: %s <program>\n", argv[0]);
71 fi = fopen("/proc/self/maps", "r");
72 CHECK_NE(fi, NULL, "fopen maps");
74 for (i = 0; i < ARRAY_SIZE(maps); i++) {
75 ret = fscanf(fi, "%lx-%lx %*s %*s %*s %*s %*s\n", &maps[i].start, &maps[i].end);
78 CHECK_EQ(ret, 2, "maps parse error");
82 CHECK_NE(map_cnt, 0, "no maps");
83 CHECK_NE(map_cnt, ARRAY_SIZE(maps), "too many maps");
85 fi = fopen(argv[1], "rb");
89 if (fread(&hdr, 1, sizeof(hdr), fi) != sizeof(hdr))
90 FAIL_PERROR("too small or");
92 if (memcmp(hdr.e_ident, ELFMAG "\x01\x01", SELFMAG + 2) != 0) {
93 fprintf(stderr, "not 32bit LE ELF?\n");
97 HDR_CHECK_EQ(e_type, ET_EXEC, "not executable");
98 // HDR_CHECK_EQ(e_machine, EM_ARM, "not ARM");
99 HDR_CHECK_EQ(e_phentsize, sizeof(Elf32_Phdr), "bad PH entry size");
100 HDR_CHECK_NE(e_phnum, 0, "no PH entries");
102 phdr = malloc(hdr.e_phnum * hdr.e_phentsize);
103 CHECK_NE(phdr, NULL, "OOM");
105 if (fread(phdr, hdr.e_phentsize, hdr.e_phnum, fi) != hdr.e_phnum)
106 FAIL_PERROR("too small or");
108 for (i = 0; i < hdr.e_phnum; i++) {
109 Elf32_Addr end_addr = phdr[i].p_vaddr + phdr[i].p_memsz;
113 if (phdr[i].p_type == PT_NOTE)
115 if (phdr[i].p_type != PT_LOAD) {
116 fprintf(stderr, "skipping section %d\n", phdr[i].p_type);
120 ret = is_range_used(maps, map_cnt, phdr[i].p_vaddr, end_addr);
122 fprintf(stderr, "segment %d (%08x-%08x) hits %08lx-%08lx in maps\n",
123 i, phdr[i].p_vaddr, end_addr, maps[ret - 1].start, maps[ret - 1].end);
127 printf("load %d %08x-%08x from %08x\n", phdr[i].p_type,
128 phdr[i].p_vaddr, end_addr, phdr[i].p_offset);
130 align = phdr[i].p_vaddr & 0xfff;
131 map_ptr = (void *)(phdr[i].p_vaddr - align);
132 ptr = mmap(map_ptr, phdr[i].p_memsz + align, PROT_READ|PROT_WRITE|PROT_EXEC,
133 MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
134 if (ptr == MAP_FAILED || ptr != map_ptr)
137 if (phdr[i].p_filesz > 0) {
138 if (fseek(fi, phdr[i].p_offset, SEEK_SET) != 0)
139 FAIL_PERROR("fseek");
140 if (fread((char *)ptr + align, 1, phdr[i].p_filesz, fi) != phdr[i].p_filesz)
141 FAIL_PERROR("too small or");
143 if (phdr[i].p_flags & PF_X)
144 do_patches((char *)ptr + align, phdr[i].p_filesz);
147 if (map_ptr < lowest_segment)
148 lowest_segment = map_ptr;
151 emu_init(lowest_segment);
153 stack_frame[0] = 1; // argc
154 stack_frame[1] = (long)argv[1];
156 stack_frame[3] = (long)environ;
159 printf("entering %08x\n", hdr.e_entry);
160 do_entry(hdr.e_entry, stack_frame, 5, NULL);