ltrace-elf.h revision cf26d59be8c23a2de97536b1f28d994e12bda004 
1#ifndef LTRACE_ELF_H
2#define LTRACE_ELF_H
3
4#include <gelf.h>
5#include <stdlib.h>
6#include "sysdep.h"
7
8struct Process;
9struct library;
10
11/* XXX Ok, the original idea was to separate the low-level ELF data
12 * from the abstract "struct library" object, but we use some of the
13 * following extensively in the back end.  Not all though.  So what we
14 * use should be move to struct library, and the rest of this
15 * structure maybe could be safely hidden in .c.  How to integrate the
16 * arch-specific bits into struct library is unclear as of now.  */
17struct ltelf {
18	int fd;
19	Elf *elf;
20	GElf_Ehdr ehdr;
21	Elf_Data *dynsym;
22	size_t dynsym_count;
23	const char *dynstr;
24	GElf_Addr plt_addr;
25	GElf_Word plt_flags;
26	size_t plt_size;
27	Elf_Data *relplt;
28	Elf_Data *plt_data;
29	size_t relplt_count;
30	Elf_Data *symtab;
31	const char *strtab;
32	const char *soname;
33	size_t symtab_count;
34	Elf_Data *opd;
35	GElf_Addr *opd_addr;
36	size_t opd_size;
37	GElf_Addr dyn_addr;
38	size_t dyn_sz;
39	size_t relplt_size;
40	GElf_Addr bias;
41	GElf_Addr entry_addr;
42	GElf_Addr base_addr;
43	struct arch_ltelf_data arch;
44};
45
46int open_elf(struct ltelf *lte, const char *filename);
47
48/* XXX is it possible to put breakpoints in VDSO and VSYSCALL
49 * pseudo-libraries?  For now we assume that all libraries can be
50 * opened via a filesystem.  BASE is ignored for ET_EXEC files.  */
51int ltelf_read_library(struct library *lib, struct Process *proc,
52		       const char *filename, GElf_Addr bias);
53
54/* Create a library object representing the main binary.  The entry
55 * point address is stored to *ENTRYP.  */
56struct library *ltelf_read_main_binary(struct Process *proc, const char *path);
57
58GElf_Addr arch_plt_sym_val(struct ltelf *, size_t, GElf_Rela *);
59
60Elf_Data *elf_loaddata(Elf_Scn *scn, GElf_Shdr *shdr);
61int elf_get_section_covering(struct ltelf *lte, GElf_Addr addr,
62			     Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr);
63int elf_get_section_type(struct ltelf *lte, GElf_Word type,
64			 Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr);
65
66/* Read, respectively, 2, 4, or 8 bytes from Elf data at given OFFSET,
67 * and store it in *RETP.  Returns 0 on success or a negative value if
68 * there's not enough data.  */
69int elf_read_u16(Elf_Data *data, size_t offset, uint16_t *retp);
70int elf_read_u32(Elf_Data *data, size_t offset, uint32_t *retp);
71int elf_read_u64(Elf_Data *data, size_t offset, uint64_t *retp);
72
73int default_elf_add_plt_entry(struct Process *proc, struct ltelf *lte,
74			      const char *a_name, GElf_Rela *rela, size_t ndx,
75			      struct library_symbol **ret);
76
77#if __WORDSIZE == 32
78#define PRI_ELF_ADDR		PRIx32
79#define GELF_ADDR_CAST(x)	(void *)(uint32_t)(x)
80#else
81#define PRI_ELF_ADDR		PRIx64
82#define GELF_ADDR_CAST(x)	(void *)(x)
83#endif
84
85#endif
86