/*
   +----------------------------------------------------------------------+
   | Zend JIT                                                             |
   +----------------------------------------------------------------------+
   | Copyright (c) The PHP Group                                          |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | [email protected] so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Dmitry Stogov <[email protected]>                              |
   |          Xinchen Hui <[email protected]>                              |
   +----------------------------------------------------------------------+
*/

#include <sys/types.h>
#include <sys/stat.h>
#if defined(__FreeBSD__) || defined(__DragonFly__)
#include <sys/sysctl.h>
#elif defined(__HAIKU__)
#include <FindDirectory.h>
#endif
#include <fcntl.h>
#include <unistd.h>

#include "zend_API.h"
#include "zend_elf.h"

static void* zend_elf_read_sect(int fd, zend_elf_sectheader *sect)
{
	void *s = emalloc(sect->size);

	if (lseek(fd, sect->ofs, SEEK_SET) < 0) {
		efree(s);
		return NULL;
	}
	if (read(fd, s, sect->size) != (ssize_t)sect->size) {
		efree(s);
		return NULL;
	}

	return s;
}

void zend_elf_load_symbols(void)
{
	zend_elf_header hdr;
	zend_elf_sectheader sect;
	int i;
#if defined(__linux__)
	int fd = open("/proc/self/exe", O_RDONLY);
#elif defined(__NetBSD__)
	int fd = open("/proc/curproc/exe", O_RDONLY);
#elif defined(__FreeBSD__) || defined(__DragonFly__)
	char path[PATH_MAX];
	size_t pathlen = sizeof(path);
	int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
	if (sysctl(mib, 4, path, &pathlen, NULL, 0) == -1) {
		return;
	}
	int fd = open(path, O_RDONLY);
#elif defined(__sun)
	int fd = open("/proc/self/path/a.out", O_RDONLY);
#elif defined(__HAIKU__)
	char path[PATH_MAX];
	if (find_path(B_APP_IMAGE_SYMBOL, B_FIND_PATH_IMAGE_PATH,
		NULL, path, sizeof(path)) != B_OK) {
		return;
	}

	int fd = open(path, O_RDONLY);
#else
	// To complete eventually for other ELF platforms.
	// Otherwise APPLE is Mach-O
	int fd = -1;
#endif

	if (fd >= 0) {
		if (read(fd, &hdr, sizeof(hdr)) == sizeof(hdr)
		 && hdr.emagic[0] == '\177'
		 && hdr.emagic[1] == 'E'
		 && hdr.emagic[2] == 'L'
		 && hdr.emagic[3] == 'F'
		 && lseek(fd, hdr.shofs, SEEK_SET) >= 0) {
			for (i = 0; i < hdr.shnum; i++) {
				if (read(fd, &sect, sizeof(sect)) == sizeof(sect)
				 && sect.type == ELFSECT_TYPE_SYMTAB) {
					uint32_t n, count = sect.size / sizeof(zend_elf_symbol);
					zend_elf_symbol *syms = zend_elf_read_sect(fd, &sect);
					char *str_tbl;

					if (syms) {
						if (lseek(fd, hdr.shofs + sect.link * sizeof(sect), SEEK_SET) >= 0
						 && read(fd, &sect, sizeof(sect)) == sizeof(sect)
						 && (str_tbl = (char*)zend_elf_read_sect(fd, &sect)) != NULL) {
							for (n = 0; n < count; n++) {
								if (syms[n].name
								 && (ELFSYM_TYPE(syms[n].info) == ELFSYM_TYPE_FUNC
								  /*|| ELFSYM_TYPE(syms[n].info) == ELFSYM_TYPE_DATA*/)
								 && (ELFSYM_BIND(syms[n].info) == ELFSYM_BIND_LOCAL
								  /*|| ELFSYM_BIND(syms[n].info) == ELFSYM_BIND_GLOBAL*/)) {
									zend_jit_disasm_add_symbol(str_tbl + syms[n].name, syms[n].value, syms[n].size);
								}
							}
							efree(str_tbl);
						}
						efree(syms);
					}
					if (lseek(fd, hdr.shofs + (i + 1) * sizeof(sect), SEEK_SET) < 0) {
						break;
					}
				}
			}
		}
		close(fd);
	}
}