/* linker.c qc object file linking Copyright (C) 2002 Bill Currie Copyright (C) 2011 Bill Currie Author: Bill Currie Date: 2002/7/3 Date: 2011/2/24 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to: Free Software Foundation, Inc. 59 Temple Place - Suite 330 Boston, MA 02111-1307, USA */ #ifdef HAVE_CONFIG_H # include "config.h" #endif static __attribute__ ((used)) const char rcsid[] = "$Id$"; #ifdef HAVE_STRING_H # include #endif #ifdef HAVE_STRINGS_H # include #endif #ifdef HAVE_UNISTD_H # include #endif #ifdef HAVE_IO_H # include #endif #include #include #include #include #include "QF/dstring.h" #include "QF/hash.h" #include "QF/pakfile.h" #include "QF/va.h" #include "codespace.h" #include "def.h" #include "defspace.h" #include "diagnostic.h" #include "emit.h" #include "expr.h" #include "immediate.h" #include "linker.h" #include "obj_file.h" #include "obj_type.h" #include "options.h" #include "qfcc.h" #include "reloc.h" #include "strpool.h" #include "type.h" static void linker_error (const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); static void linker_warning (const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); static void def_error (qfo_def_t *def, const char *fmt, ...) __attribute__ ((format (printf, 2, 3))); static void def_warning (qfo_def_t *def, const char *fmt, ...) __attribute__ ((used, format (printf, 2, 3))); typedef struct builtin_sym_s { const char *name; type_t *type; unsigned flags; } builtin_sym_t; static builtin_sym_t builtin_symbols[] __attribute__ ((used)) = { {".zero", &type_zero, QFOD_NOSAVE}, {".return", &type_param, QFOD_NOSAVE}, {".param_0", &type_param, QFOD_NOSAVE}, {".param_1", &type_param, QFOD_NOSAVE}, {".param_2", &type_param, QFOD_NOSAVE}, {".param_3", &type_param, QFOD_NOSAVE}, {".param_4", &type_param, QFOD_NOSAVE}, {".param_5", &type_param, QFOD_NOSAVE}, {".param_6", &type_param, QFOD_NOSAVE}, {".param_7", &type_param, QFOD_NOSAVE}, }; typedef struct defref_s { struct defref_s *next; qfo_def_t **def_list; int def; int space; } defref_t; #define REF(r) (work->spaces[(r)->space].defs + (r)->def) static defref_t *free_defrefs; static hashtab_t *extern_defs; static hashtab_t *defined_defs; static hashtab_t *extern_type_defs; static hashtab_t *defined_type_defs; static qfo_mspace_t *qfo_type_defs; static qfo_t *work; static defref_t **work_defrefs; static int num_work_defrefs; static strpool_t *work_strings; static codespace_t *work_code; static defspace_t *work_near_data; static defspace_t *work_far_data; static defspace_t *work_entity_data; static defspace_t *work_type_data; static dstring_t *linker_current_file; #define QFOSTR(q,s) QFO_GETSTR (q, s) #define WORKSTR(s) QFOSTR (work, s) /** Produce an error message for defs with mismatched types. \param def The new def. \param prev The previous definition. */ static void linker_type_mismatch (qfo_def_t *def, qfo_def_t *prev) { def_error (def, "type mismatch for `%s' `%s'", WORKSTR (def->name), QFO_TYPESTR (work, def->type)); def_error (prev, "previous definition `%s'", QFO_TYPESTR (work, prev->type)); } /** Create a new def reference. References are required to avoid problems with realloc moving things around. The \a def must be in the \a space, and the \a space must be in the \c work qfo. \param def The def for which the reference will be created. \param space The defspace in \c work which holds \a def. \return The new reference. */ static defref_t * get_defref (qfo_def_t *def, qfo_mspace_t *space) { defref_t *defref; ALLOC (16384, defref_t, defrefs, defref); defref->def = def - space->defs; defref->space = space - work->spaces; return defref; } static const char * defs_get_key (void *_r, void *unused) { defref_t *r = (defref_t *)_r; qfo_def_t *d = REF (r); return WORKSTR (d->name); } /** Add a string to the working qfo string pool. If the string is already in the string pool, the already existing string index will be returned instead of adding a second copy of the string. The strings space in the working qfo is kept up to date. \param str The string to add. \return The string offset in the working qfo string pool. */ static string_t add_string (const char *str) { string_t new; new = strpool_addstr (work_strings, str); work->spaces[qfo_strings_space].d.strings = work_strings->strings; work->spaces[qfo_strings_space].data_size = work_strings->size; return new; } /** Resolve an external def with its global definition. The types of the external def and the global def must match. The offset and flags of the global def are copied to the external def. \fixme handle cross-space resolutions. \fixme copy relocs from \a ext to \a def and "delete" \a ext? \param ext The external def. \param def The global definition. */ static void resolve_external_def (defref_t *ext, defref_t *def) { if (REF (ext)->type != REF (def)->type) { linker_type_mismatch (REF (ext), REF (def)); return; } if (def->space != ext->space) internal_error (0, "help, help!"); REF (ext)->offset = REF (def)->offset; REF (ext)->flags = REF (def)->flags; } static void process_def (defref_t *ref, qfo_mspace_t *space) { qfo_def_t *def; defref_t *r; const char *name; def = REF (ref); name = WORKSTR (def->name); r = Hash_Find (defined_defs, name); if (def->flags & QFOD_EXTERNAL) { if (!def->num_relocs) return; if (r) { resolve_external_def (ref, r); } else { Hash_Add (extern_defs, ref); } } else if (def->flags & QFOD_GLOBAL) { if (r) { if (REF (r)->flags & QFOD_SYSTEM) { if (def->type != REF (r)->type) { linker_type_mismatch (def, REF (r)); return; } /// System defs may be redefined only once. REF (r)->flags &= ~QFOD_SYSTEM; if (ref->space != r->space) internal_error (0, "help, help!"); //FIXME copy stuff from new def to existing def??? def->offset = REF(r)->offset; def->flags = REF(r)->flags; } else { def_error (def, "%s redefined", WORKSTR (def->name)); def_error (REF (r), "previous definition"); } return; } Hash_Add (defined_defs, ref); if (!(def->flags & QFOD_LOCAL)) def->offset += space->data_size; while ((r = Hash_Del (extern_defs, name))) resolve_external_def (r, ref); } } static int add_defs (qfo_t *qfo, qfo_mspace_t *space, qfo_mspace_t *dest_space) { int count = space->num_defs; int size; int i; qfo_def_t *idef; qfo_def_t *odef; defref_t *ref; qfot_type_t *type; size = (num_work_defrefs + count) * sizeof (defref_t *); work_defrefs = realloc (work_defrefs, size); size = (dest_space->num_defs + count) * sizeof (qfo_def_t); dest_space->defs = realloc (dest_space->defs, size); idef = space->defs; odef = dest_space->defs + dest_space->num_defs; for (i = 0; i < count; i++, idef++, odef++) { *odef = *idef; idef->offset = num_work_defrefs; // so def can be found odef->name = add_string (QFOSTR (qfo, idef->name)); odef->file = add_string (QFOSTR (qfo, idef->file)); type = (qfot_type_t *) (char *) (qfo_type_defs->d.data + idef->type); odef->type = type->t.class; ref = get_defref (odef, dest_space); work_defrefs[num_work_defrefs++] = ref; process_def (ref, dest_space); } dest_space->num_defs += count; return count; } /** Add all the strings in the strings space to the working qfo. \param strings The strings space of the qfo being linked. */ static void add_qfo_strings (qfo_mspace_t *strings) { const char *str = strings->d.strings; while (str - strings->d.strings < strings->data_size) { add_string (str); while (str - strings->d.strings < strings->data_size && *str) str++; str++; // advance past the terminating nul } } /** Add the code in the code space to the working qfo. \param code The code space of the qfo being linked. */ static void add_code (qfo_mspace_t *code) { codespace_addcode (work_code, code->d.code, code->data_size); work->spaces[qfo_code_space].d.code = work_code->code; work->spaces[qfo_code_space].data_size = work_code->size; } /** Add the data in a data space to the working qfo. \param data A data space of the qfo being linked. */ static void add_data (int space, qfo_mspace_t *data) { defspace_t *work_spaces[qfo_num_spaces] = { 0, 0, 0, work_near_data, work_far_data, work_entity_data, 0, }; if (space < 0 || space >= qfo_num_spaces || !work_spaces[space]) internal_error (0, "bad space for add_data (): %d", space); defspace_add_data (work_spaces[space], data->d.data, data->data_size); work->spaces[space].d.data = work_spaces[space]->data; work->spaces[space].data_size = work_spaces[space]->size; } /** Add a defspace to the working qfo. \param qfo The qfo being linked. \param space The defspace from \a qfo that will be added to the working qfo. */ static void add_space (qfo_t *qfo, qfo_mspace_t *space) { qfo_mspace_t *ws; if (space->type != qfos_data) internal_error (0, "bad space type for add_space (): %d", space->type); space->id = work->num_spaces++; // so the space in work can be found work->spaces = realloc (work->spaces, work->num_spaces * sizeof (qfo_mspace_t)); ws = &work->spaces[space->id]; memset (ws, 0, sizeof (qfo_mspace_t)); ws->type = space->type; if (space->num_defs) add_defs (qfo, space, ws); if (space->d.data) { int size = space->data_size * sizeof (pr_type_t); ws->d.data = malloc (size); memcpy (ws->d.data, space->d.data, size); } ws->data_size = space->data_size; ws->id = space->id; } static __attribute__ ((used)) void define_def (const char *name, etype_t basic_type, const char *full_type, unsigned flags, int size, int v) { } /** Initialize the linker state. */ void linker_begin (void) { linker_current_file = dstring_newstr (); extern_defs = Hash_NewTable (16381, defs_get_key, 0, 0); defined_defs = Hash_NewTable (16381, defs_get_key, 0, 0); extern_type_defs = Hash_NewTable (16381, defs_get_key, 0, 0); defined_type_defs = Hash_NewTable (16381, defs_get_key, 0, 0); work = qfo_new (); work->spaces = calloc (qfo_num_spaces, sizeof (qfo_mspace_t)); work->num_spaces = qfo_num_spaces; work->spaces[qfo_null_space].type = qfos_null; work->spaces[qfo_strings_space].type = qfos_string; work->spaces[qfo_code_space].type = qfos_code; work->spaces[qfo_near_data_space].type = qfos_data; work->spaces[qfo_far_data_space].type = qfos_data; work->spaces[qfo_entity_space].type = qfos_entity; work->spaces[qfo_type_space].type = qfos_type; // adding data will take care of connecting the work qfo spaces with // the actual space data work_strings = strpool_new (); work_code = codespace_new (); work_near_data = defspace_new (); work_far_data = defspace_new (); work_entity_data = defspace_new (); work_type_data = defspace_new (); } typedef int (*space_func) (qfo_t *qfo, qfo_mspace_t *space, int pass); static int process_null (qfo_t *qfo, qfo_mspace_t *space, int pass) { if (pass != 0) return 0; if (space->defs || space->num_defs || space->d.data || space->data_size || space->id) { linker_error ("non-null null space"); return 1; } return 0; } static int process_code (qfo_t *qfo, qfo_mspace_t *space, int pass) { if (pass != 1) return 0; if (space->defs || space->num_defs) { linker_error ("defs in code space"); return 1; } if (space->id != qfo_code_space) linker_warning ("hmm, unexpected code space. *shrug*"); add_code (space); return 0; } static int process_data (qfo_t *qfo, qfo_mspace_t *space, int pass) { if (pass != 1) return 0; if (space->id == qfo_near_data_space) { add_defs (qfo, space, work->spaces + qfo_near_data_space); add_data (qfo_near_data_space, space); } else if (space->id == qfo_far_data_space) { add_defs (qfo, space, work->spaces + qfo_far_data_space); add_data (qfo_far_data_space, space); } else { add_space (qfo, space); } return 0; } static int process_strings (qfo_t *qfo, qfo_mspace_t *space, int pass) { if (pass != 0) return 0; if (space->defs || space->num_defs) { linker_error ("defs in strings space"); return 1; } add_qfo_strings (space); return 0; } static int process_entity (qfo_t *qfo, qfo_mspace_t *space, int pass) { if (pass != 1) return 0; add_data (qfo_entity_space, space); return 0; } static pointer_t transfer_type (qfo_t *qfo, qfo_mspace_t *space, pointer_t type_offset) { qfot_type_t *type; int i; type = (qfot_type_t *) (char *) &space->d.data[type_offset]; if (type->ty < 0) return type->t.class; switch ((ty_type_e) type->ty) { case ty_none: if (type->t.type == ev_func) { int count; qfot_func_t *f = &type->t.func; pointer_t *p; count = f->num_params; if (count < 0) count = ~count; //ones complement f->return_type = transfer_type (qfo, space, f->return_type); for (i = 0, p = f->param_types; i < count; i++, p++) *p = transfer_type (qfo, space, *p); } else if (type->t.type == ev_pointer || type->t.type == ev_field) { qfot_fldptr_t *fp = &type->t.fldptr; fp->aux_type = transfer_type (qfo, space, fp->aux_type); } break; case ty_struct: case ty_union: case ty_enum: type->t.strct.tag = add_string (QFOSTR (qfo, type->t.strct.tag)); for (i = 0; i < type->t.strct.num_fields; i++) { qfot_var_t *field = &type->t.strct.fields[i]; field->type = transfer_type (qfo, space, field->type); field->name = add_string (QFOSTR (qfo, field->name)); } break; case ty_array: type->t.array.type = transfer_type (qfo, space, type->t.array.type); break; case ty_class: //FIXME this is broken break; } type_offset = defspace_alloc_loc (work_type_data, type->size); memcpy (work_type_data->data + type_offset, type, type->size * sizeof (pr_type_t)); type->ty = -1; type->t.class = type_offset; return type_offset; } static int process_type (qfo_t *qfo, qfo_mspace_t *space, int pass) { int i; int size; qfo_def_t *def; qfo_def_t *type_def; qfo_mspace_t *type_space; qfot_type_t *type; const char *name; defref_t *ref; pointer_t offset; if (pass != 0) return 0; if (qfo_type_defs) { linker_error ("type space already defined"); return 1; } qfo_type_defs = space; type_space = &work->spaces[qfo_type_space]; size = (type_space->num_defs + space->num_defs) * sizeof (qfo_def_t); type_space->defs = realloc (type_space->defs, size); // first pass: check for already defined types for (i = 0, def = space->defs; i < space->num_defs; i++, def++) { name = QFOSTR (qfo, def->name); type = (qfot_type_t *) (char *) &space->d.data[def->offset]; if ((ref = Hash_Find (defined_type_defs, name))) { type->ty = -1; type->t.class = REF (ref)->offset; continue; } } // second pass: transfer any new types for (i = 0, def = space->defs; i < space->num_defs; i++, def++) { name = QFOSTR (qfo, def->name); type = (qfot_type_t *) (char *) &space->d.data[def->offset]; if (type->ty < 0) continue; offset = transfer_type (qfo, space, def->offset); type_def = type_space->defs + type_space->num_defs++; memset (type_def, 0, sizeof (*type_def)); type_def->name = add_string (name); type_def->offset = offset; ref = get_defref (type_def, type_space); Hash_Add (defined_type_defs, ref); while ((ref = Hash_Del (extern_type_defs, name))) { REF (ref)->flags = 0; REF (ref)->offset = type_def->offset; } } size = type_space->num_defs * sizeof (qfo_def_t); type_space->defs = realloc (type_space->defs, size); type_space->d.data = work_type_data->data; type_space->data_size = work_type_data->size; return 0; } static int linker_add_qfo (qfo_t *qfo) { static space_func funcs[] = { process_null, process_code, process_data, process_strings, process_entity, process_type, }; int i; int pass; qfo_mspace_t *space; qfo_type_defs = 0; for (pass = 0; pass < 2; pass++) { for (i = 0, space = qfo->spaces; i < qfo->num_spaces; i++, space++) { if (space->type < 0 || space->type > qfos_type) { linker_error ("bad space type"); return 1; } if (funcs[space->type] (qfo, space, pass)) return 1; } } return 0; } int linker_add_object_file (const char *filename) { qfo_t *qfo; dsprintf (linker_current_file, "%s", filename); qfo = qfo_open (filename); if (!qfo) { linker_error ("error opening"); return 1; } if (qfo->num_spaces < qfo_num_spaces || qfo->spaces[qfo_null_space].type != qfos_null || qfo->spaces[qfo_strings_space].type != qfos_string || qfo->spaces[qfo_code_space].type != qfos_code || qfo->spaces[qfo_near_data_space].type != qfos_data || qfo->spaces[qfo_far_data_space].type != qfos_data || qfo->spaces[qfo_entity_space].type != qfos_entity || qfo->spaces[qfo_type_space].type != qfos_type) { linker_error ("missing or mangled standard spaces"); return 1; } if (options.verbosity >= 2) puts (filename); linker_add_qfo (qfo); qfo_delete (qfo); return 0; } typedef struct path_s { struct path_s *next; const char *path; } path_t; static path_t *path_head; static path_t **path_tail = &path_head; int linker_add_lib (const char *libname) { pack_t *pack = 0; path_t start = {path_head, "."}; path_t *path = &start; const char *path_name = 0; int i, j; int did_something; if (strncmp (libname, "-l", 2) == 0) { while (path) { path_name = va ("%s/lib%s.a", path->path, libname + 2); pack = pack_open (path_name); if (pack) break; if (errno != ENOENT) { if (errno) perror (libname); return 1; } path = path->next; } } else { path_name = libname; pack = pack_open (path_name); } if (!pack) { if (errno) perror (libname); return 1; } if (options.verbosity > 1) puts (path_name); do { did_something = 0; for (i = 0; i < pack->numfiles; i++) { QFile *f; qfo_t *qfo; dsprintf (linker_current_file, "%s(%s)", path_name, pack->files[i].name); f = Qsubopen (path_name, pack->files[i].filepos, pack->files[i].filelen, 1); qfo = qfo_read (f); Qclose (f); if (!qfo) { linker_error ("error opening"); return 1; } for (j = 0; j < qfo->num_defs; j++) { qfo_def_t *def = qfo->defs + j; if ((def->flags & QFOD_GLOBAL) && !(def->flags & QFOD_EXTERNAL) && Hash_Find (extern_defs, QFOSTR (qfo, def->name))) { if (options.verbosity >= 2) printf ("adding %s because of %s\n", pack->files[i].name, QFOSTR (qfo, def->name)); linker_add_qfo (qfo); did_something = 1; break; } } qfo_delete (qfo); } } while (did_something); pack_del (pack); return 0; } static __attribute__ ((used)) void undefined_def (qfo_def_t *def) { #if 0 qfo_def_t line_def; pr_int_t i; qfo_reloc_t *reloc = relocs.relocs + def->relocs; for (i = 0; i < def->num_relocs; i++, reloc++) { if ((reloc->type == rel_op_a_def || reloc->type == rel_op_b_def || reloc->type == rel_op_c_def || reloc->type == rel_op_a_def_ofs || reloc->type == rel_op_b_def_ofs || reloc->type == rel_op_c_def_ofs) && lines.lines) { qfo_func_t *func = funcs.funcs; qfo_func_t *best = func; pr_int_t best_dist = reloc->offset - func->code; pr_lineno_t *line; while (best_dist && func - funcs.funcs < funcs.num_funcs) { if (func->code <= reloc->offset) { if (best_dist < 0 || reloc->offset - func->code < best_dist) { best = func; best_dist = reloc->offset - func->code; } } func++; } line = lines.lines + best->line_info; line_def.file = best->file; line_def.line = best->line; if (!line->line && line->fa.func == (pr_uint_t) (best - funcs.funcs)) { while (line - lines.lines < lines.num_lines - 1 && line[1].line && line[1].fa.addr <= (pr_uint_t) reloc->offset) line++; line_def.line = line->line + best->line; } def_error (&line_def, "undefined symbol %s", STRING (def->name)); } else { def_error (def, "undefined symbol %s", STRING (def->name)); } } #endif } qfo_t * linker_finish (void) { #if 0 defref_t **undef_defs, **defref; qfo_t *qfo; if (!options.partial_link) { int did_self = 0, did_this = 0; undef_defs = (defref_t **) Hash_GetList (extern_defs); for (defref = undef_defs; *defref; defref++) { qfo_def_t *def = deref_def (*defref, &global_defs); const char *name = STRING (def->name); if (strcmp (name, ".self") == 0 && !did_self) { defref_t *_d = Hash_Find (defined_defs, "self"); if (_d) { // qfo_def_t *d = deref_def (_d, &global_defs); // if (d->basic_type == ev_entity) // def_warning (d, "@self and self used together"); } define_def (".self", ev_entity, "E", 0, 1, 0); did_self = 1; } else if (strcmp (name, ".this") == 0 && !did_this) { entity_base = 0; define_def (".this", ev_field, "F@", QFOD_NOSAVE, 1, entity->size); defspace_add_data (entity, 0, 1); did_this = 1; } } free (undef_defs); undef_defs = (defref_t **) Hash_GetList (extern_defs); for (defref = undef_defs; *defref; defref++) { qfo_def_t *def = deref_def (*defref, &global_defs); undefined_def (def); } free (undef_defs); if (pr.error_count) return 0; } merge_defgroups (); fixup_relocs (); qfo = qfo_new (); qfo_add_code (qfo, code->code, code->size); qfo_add_data (qfo, data->data, data->size); qfo_add_far_data (qfo, far_data->data, far_data->size); qfo_add_strings (qfo, strings->strings, strings->size); qfo_add_relocs (qfo, final_relocs.relocs, final_relocs.num_relocs); qfo_add_defs (qfo, defs.defs, defs.num_defs); qfo_add_funcs (qfo, funcs.funcs, funcs.num_funcs); qfo_add_lines (qfo, lines.lines, lines.num_lines); qfo_add_types (qfo, type_strings->strings, type_strings->size); // qfo->entity_fields = entity->size; return qfo; #endif return work; } void linker_add_path (const char *path) { path_t *p = malloc (sizeof (path_t)); p->next = 0; p->path = path; *path_tail = p; path_tail = &p->next; } static void def_error (qfo_def_t *def, const char *fmt, ...) { va_list args; static dstring_t *string; if (!string) string = dstring_new (); va_start (args, fmt); dvsprintf (string, fmt, args); va_end (args); pr.source_file = def->file; pr.source_line = def->line; // pr.strings = strings; error (0, "%s", string->str); } static void def_warning (qfo_def_t *def, const char *fmt, ...) { va_list args; static dstring_t *string; if (!string) string = dstring_new (); va_start (args, fmt); dvsprintf (string, fmt, args); va_end (args); pr.source_file = def->file; pr.source_line = def->line; // pr.strings = strings; warning (0, "%s", string->str); } static void linker_warning (const char *fmt, ...) { va_list args; fprintf (stderr, "%s: warning: ", linker_current_file->str); va_start (args, fmt); vfprintf (stderr, fmt, args); va_end (args); fputs ("\n", stderr); if (options.warnings.promote) pr.error_count++; } static void linker_error (const char *fmt, ...) { va_list args; fprintf (stderr, "%s: ", linker_current_file->str); va_start (args, fmt); vfprintf (stderr, fmt, args); va_end (args); fputs ("\n", stderr); pr.error_count++; }