system.c File Reference

🍎 macOS system utilities and backtrace symbol resolution More...

Go to the source code of this file.

Functions
int	get_binary_file_address_offsets (const void *addr, platform_binary_match_t *matches, int max_matches)
	Get binary that contains address on macOS via dyld.

Detailed Description

🍎 macOS system utilities and backtrace symbol resolution

Definition in file macos/system.c.

Function Documentation

get_binary_file_address_offsets()

int get_binary_file_address_offsets	(	const void *	addr,
		platform_binary_match_t *	matches,
		int	max_matches
	)

Get binary that contains address on macOS via dyld.

Iterates through dyld-loaded images to find which one contains the given runtime address. Returns the file offset within that image, which is passed to llvm-symbolizer for symbol resolution.

Parameters

addr	Runtime address from backtrace
matches	Output array for matches (path, offset, is_project_lib)
max_matches	Maximum number of matches to store

Returns

Number of matches found (0, 1, or rarely 2)

Definition at line 54 of file macos/system.c.

                                                                                                         {
  int count = 0;
  uintptr_t addr_int = (uintptr_t)addr;
 
  uint32_t image_count = _dyld_image_count();
  for (uint32_t i = 0; i < image_count && count < max_matches; i++) {
    const char *image_name = _dyld_get_image_name(i);
    const struct mach_header_64 *header = (const struct mach_header_64 *)_dyld_get_image_header(i);
    intptr_t slide = _dyld_get_image_vmaddr_slide(i);
 
    if (!header || !image_name) {
      continue;
    }
 
    // Calculate image size from mach header
    uint64_t image_size = get_image_size_from_header(header);
    if (image_size == 0) {
      continue;
    }
 
    // Base address is header address + slide
    uintptr_t base = (uintptr_t)header + slide;
    uintptr_t end = base + image_size;
 
    // Check if address falls within this image
    if (addr_int >= base && addr_int < end) {
      strncpy(matches[count].path, image_name, PLATFORM_MAX_PATH_LENGTH - 1);
      matches[count].path[PLATFORM_MAX_PATH_LENGTH - 1] = '\0';
      matches[count].file_offset = addr_int - base;
 
#ifndef NDEBUG
      log_debug("[macOS dyld] addr=%p matches %s (offset=%lx, base=%p, slide=%ld)", addr, image_name,
                matches[count].file_offset, (void *)base, slide);
#endif
      count++;
    }
  }
 
  return count;
}

References PLATFORM_MAX_PATH_LENGTH.