diff options
| -rw-r--r-- | gold/main.cc | 88 |
1 files changed, 87 insertions, 1 deletions
diff --git a/gold/main.cc b/gold/main.cc index 507e5dd..5112223 100644 --- a/gold/main.cc +++ b/gold/main.cc @@ -39,6 +39,85 @@ using namespace gold; +// This function emits the commandline to a hard-coded file in temp. +// This is useful for debugging since ld is typically invoked by gcc, +// so its commandline is not always easy to extract. You should be +// able to run 'gcc -B... foo.o -o foo' to invoke this linker the +// first time, and then /tmp/ld-run-foo.sh to invoke it on subsequent +// runes. "/tmp/ld-run-foo.sh debug" will run the linker inside gdb +// (or whatever value the environment variable GDB is set to), for +// even easier debugging. Since this is a debugging-only tool, and +// creates files, it is only turned on when the user explicitly asks +// for it, by compiling with -DDEBUG. Do not do this for release +// versions of the linker! + +#ifdef DEBUG +#include <stdio.h> +#include <sys/stat.h> // for chmod() + +static std::string +collect_argv(int argc, char** argv) +{ + // This is used by write_debug_script(), which wants the unedited argv. + std::string args; + for (int i = 0; i < argc; ++i) + { + args.append(" '"); + // Now append argv[i], but with all single-quotes escaped + const char* argpos = argv[i]; + while (1) + { + const int len = strcspn(argpos, "'"); + args.append(argpos, len); + if (argpos[len] == '\0') + break; + args.append("'\"'\"'"); + argpos += len + 1; + } + args.append("'"); + } + return args; +} + +static void +write_debug_script(std::string filename_str, + const char* argv_0, const char* args) +{ + size_t slash = filename_str.rfind('/'); + if (slash != std::string::npos) + filename_str = filename_str.c_str() + slash + 1; + filename_str = std::string("/var/tmp/ld-run-") + filename_str + ".sh"; + const char* filename = filename_str.c_str(); + FILE* fp = fopen(filename, "w"); + if (fp) + { + fprintf(fp, "[ \"$1\" = debug ] && PREFIX=\"${GDB-/home/build/static/projects/tools/gdb} --annotate=3 --fullname %s --args\" && shift\n", argv_0); + fprintf(fp, "$PREFIX%s $*\n", args); + fclose(fp); + chmod(filename, 0755); + } + else + filename = "[none]"; + fprintf(stderr, "Welcome to gold! Commandline written to %s.\n", filename); + fflush(stderr); +} + +#else // !defined(DEBUG) + +static inline std::string +collect_argv(int, char**) +{ + return ""; +} + +static inline void +write_debug_script(std::string, const char*, const char*) +{ +} + +#endif // !defined(DEBUG) + + int main(int argc, char** argv) { @@ -53,6 +132,9 @@ main(int argc, char** argv) program_name = argv[0]; + // This is used by write_debug_script(), which wants the unedited argv. + std::string args = collect_argv(argc, argv); + Errors errors(program_name); // Initialize the global parameters, to let random code get to the @@ -74,6 +156,10 @@ main(int argc, char** argv) // Store some options in the globally accessible parameters. set_parameters_from_options(&command_line.options()); + // Do this as early as possible (since it prints a welcome message). + write_debug_script(command_line.options().output_file_name(), + program_name, args.c_str()); + // The work queue. Workqueue workqueue(command_line.options()); @@ -82,7 +168,7 @@ main(int argc, char** argv) // The symbol table. We're going to guess here how many symbols // we're going to see based on the number of input files. Even when - // this is off, it means at worse we don't quite optimize hashtable + // this is off, it means at worst we don't quite optimize hashtable // resizing as well as we could have (perhap using more memory). Symbol_table symtab(command_line.number_of_input_files() * 1024, command_line.options().version_script()); |