/*
* Edit the ELF file residing at @p path, changing all occurrences of
* the path @p server_path to @p client_path in the debugging info.
*
* We're a bit sloppy about that; rather than properly parsing
* the DWARF debug info, finding the DW_AT_comp_dir (compilation working
* directory) field and the DW_AT_name (source file name) field,
* we just do a search-and-replace in the ".debug_info" and ".debug_str"
* sections. But this is good enough.
*
* Returns 0 on success (whether or not the ".debug_info" and ".debug_str"
* sections were found or updated).
* Returns 1 on serious error that should cause distcc to fail.
*/
int dcc_fix_debug_info(const char *path, const char *client_path,
const char *server_path)
{
#ifndef HAVE_ELF_H
rs_trace("no <elf.h>, so can't change %s to %s in debug info for %s",
server_path, client_path, path);
return 0;
#else
/*
* We can only safely replace a string with another of exactly
* the same length. (Replacing a string with a shorter string
* results in errors from gdb.)
* So we append trailing slashes on the client side path.
*/
size_t client_path_len = strlen(client_path);
size_t server_path_len = strlen(server_path);
assert(client_path_len <= server_path_len);
char *client_path_plus_slashes = malloc(server_path_len + 1);
if (!client_path_plus_slashes) {
rs_log_crit("failed to allocate memory");
return 1;
}
strcpy(client_path_plus_slashes, client_path);
while (client_path_len < server_path_len) {
client_path_plus_slashes[client_path_len++] = '/';
}
client_path_plus_slashes[client_path_len] = '\0';
rs_log_info("client_path_plus_slashes = %s", client_path_plus_slashes);
return update_debug_info(path, server_path, client_path_plus_slashes);
#endif
}
/*
* get_debug_info returns the debug information for the case when the instruction
* at the given program counter is being executed.
*/
struct DebugInfo get_debug_info(int pc)
{
struct DebugInfo info;
struct SymbolTableEntry *stab_entry = NULL;
init_debug_info(&info);
stab_entry = (struct SymbolTableEntry *) STAB_BEGIN;
while (stab_entry != STAB_END) {
update_debug_info(&info, stab_entry);
if ((uint32_t) info.source_line_address >= (uint32_t) pc)
break;
stab_entry++;
}
return info;
}
