/* * $OpenBSD: warnings.c,v 1.10 2003/04/16 02:15:10 deraadt Exp $*/ /* */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if __STDC__ #include #else #include #endif #include "ld.h" static int reported_undefineds; /* * Print the filename of ENTRY on OUTFILE (a stdio stream), * and then a newline. */ void prline_file_name(struct file_entry *entry, FILE *outfile) { print_file_name (entry, outfile); fprintf (outfile, "\n"); } /* * Print the filename of ENTRY on OUTFILE (a stdio stream). */ void print_file_name(struct file_entry *entry, FILE *outfile) { if (entry == NULL) { fprintf (outfile, "NULL"); } if (entry->superfile) { print_file_name (entry->superfile, outfile); fprintf (outfile, "(%s)", entry->filename); } else fprintf (outfile, "%s", entry->filename); } /* * Return the filename of entry as a string (malloc'd for the purpose) */ char * get_file_name(struct file_entry *entry) { char *result, *supfile; size_t len; if (entry == NULL) { return (char *)strdup("NULL"); } if (entry->superfile) { supfile = get_file_name(entry->superfile); len = strlen(supfile) + 1 + strlen(entry->filename) + 2; result = (char *) xmalloc(len); (void)snprintf(result, len, "%s(%s)", supfile, entry->filename); free(supfile); } else { result = (char *)xstrdup(entry->filename); } return result; } /* Print a complete or partial map of the output file. */ static void describe_file_sections(struct file_entry *, void *); static void list_file_locals(struct file_entry *, void *); void print_symbols(FILE *outfile) { fprintf(outfile, "\nFiles:\n\n"); each_file(describe_file_sections, (void *)outfile); fprintf(outfile, "\nGlobal symbols:\n\n"); FOR_EACH_SYMBOL(i, sp) { fprintf(outfile, " %s: ", sp->name); if (!(sp->flags & GS_REFERENCED)) fprintf(outfile, "unreferenced"); else if (sp->so_defined) fprintf(outfile, "sodefined"); else if (!sp->defined) fprintf(outfile, "undefined"); else if (sp->defined == (N_UNDF|N_EXT)) fprintf(outfile, "common: size %#x", sp->common_size); else fprintf(outfile, "type %d, value %#lx, size %#x", sp->defined, sp->value, sp->size); if (sp->alias) fprintf(outfile, ", aliased to %s", sp->alias->name); fprintf(outfile, "\n"); } END_EACH_SYMBOL; each_file(list_file_locals, (void *)outfile); } static void describe_file_sections(struct file_entry *entry, void *arg) { FILE *outfile = arg; fprintf(outfile, " "); print_file_name(entry, outfile); if (entry->flags & (E_JUST_SYMS | E_DYNAMIC)) fprintf(outfile, " symbols only\n"); else fprintf(outfile, " text %x(%x), data %x(%x), bss %x(%x) hex\n", entry->text_start_address, entry->header.a_text, entry->data_start_address, entry->header.a_data, entry->bss_start_address, entry->header.a_bss); } static void list_file_locals(struct file_entry *entry, void *arg) { FILE *outfile = arg; struct localsymbol *lsp, *lspend; entry->strings = (char *)alloca(entry->string_size); read_entry_strings (file_open(entry), entry); fprintf (outfile, "\nLocal symbols of "); print_file_name (entry, outfile); fprintf (outfile, ":\n\n"); lspend = entry->symbols + entry->nsymbols; for (lsp = entry->symbols; lsp < lspend; lsp++) { struct nlist *p = &lsp->nzlist.nlist; /* * If this is a definition, * update it if necessary by this file's start address. */ if (!(p->n_type & (N_STAB | N_EXT))) fprintf(outfile, " %s: 0x%lx\n", entry->strings + p->n_un.n_strx, p->n_value); } entry->strings = 0; /* All done with them. */ } /* Static vars for do_warnings and subroutines of it */ static int list_unresolved_refs; /* List unresolved refs */ static int list_multiple_defs; /* List multiple definitions */ static struct line_debug_entry *init_debug_scan(int, struct file_entry *); static int next_debug_entry(int, struct line_debug_entry *); /* * Structure for communication between do_file_warnings and it's * helper routines. Will in practice be an array of three of these: * 0) Current line, 1) Next line, 2) Source file info. */ struct line_debug_entry { int line; char *filename; struct localsymbol *sym; }; /* * Helper routines for do_file_warnings. */ /* * Return an integer less than, equal to, or greater than 0 as per the * relation between the two relocation entries. Used by qsort. */ static int reloc_cmp(const void *arg1, const void *arg2) { const struct relocation_info *rel1 = arg1; const struct relocation_info *rel2 = arg2; return RELOC_ADDRESS(rel1) - RELOC_ADDRESS(rel2); } /* * Moves to the next debugging symbol in the file. USE_DATA_SYMBOLS * determines the type of the debugging symbol to look for (DSLINE or * SLINE). STATE_POINTER keeps track of the old and new locatiosn in * the file. It assumes that state_pointer[1] is valid; ie * that it.sym points into some entry in the symbol table. If * state_pointer[1].sym == 0, this routine should not be called. */ static int next_debug_entry(int use_data_symbols, struct line_debug_entry state_pointer[3]) { struct line_debug_entry *current = state_pointer, *next = state_pointer + 1, /* Used to store source file */ *source = state_pointer + 2; struct file_entry *entry = (struct file_entry *)source->sym; struct localsymbol *lspend = entry->symbols + entry->nsymbols; current->sym = next->sym; current->line = next->line; current->filename = next->filename; while (++(next->sym) < lspend) { struct nlist *np = &next->sym->nzlist.nlist; /* * n_type is a char, and N_SOL, N_EINCL and N_BINCL are > 0x80, * so may look negative...therefore, must mask to low bits */ switch (np->n_type & 0xff) { case N_SLINE: if (use_data_symbols) continue; next->line = np->n_desc; return 1; case N_DSLINE: if (!use_data_symbols) continue; next->line = np->n_desc; return 1; #ifdef HAVE_SUN_STABS case N_EINCL: next->filename = source->filename; continue; #endif case N_SO: source->filename = np->n_un.n_strx + entry->strings; source->line++; #ifdef HAVE_SUN_STABS case N_BINCL: #endif case N_SOL: next->filename = np->n_un.n_strx + entry->strings; default: continue; } } next->sym = (struct localsymbol *)0; return 0; } /* * Create a structure to save the state of a scan through the debug symbols. * USE_DATA_SYMBOLS is set if we should be scanning for DSLINE's instead of * SLINE's. ENTRY is the file entry which points at the symbols to use. */ static struct line_debug_entry * init_debug_scan(int use_data_symbols, struct file_entry *entry) { struct localsymbol *lsp, *lspend; struct line_debug_entry *state_pointer, *current, *next, *source; state_pointer = (struct line_debug_entry *) xmalloc(3 * sizeof(*state_pointer)); current = state_pointer, next = state_pointer + 1, source = state_pointer + 2; /* Used to store source file */ lspend = entry->symbols+entry->nsymbols; for (lsp = entry->symbols; lsp < lspend; lsp++) if (lsp->nzlist.nlist.n_type == N_SO) break; if (lsp >= lspend) { /* I believe this translates to "We lose" */ current->filename = next->filename = entry->filename; current->line = next->line = -1; current->sym = next->sym = (struct localsymbol *)0; return state_pointer; } next->line = source->line = 0; next->filename = source->filename = (lsp->nzlist.nlist.n_un.n_strx + entry->strings); source->sym = (struct localsymbol *)entry; next->sym = lsp; /* To setup next */ next_debug_entry(use_data_symbols, state_pointer); if (!next->sym) { /* No line numbers for this section; */ /* setup output results as appropriate */ if (source->line) { current->filename = source->filename = entry->filename; current->line = -1; /* Don't print lineno */ } else { current->filename = source->filename; current->line = 0; } return state_pointer; } /* To setup current */ next_debug_entry(use_data_symbols, state_pointer); return state_pointer; } /* * Takes an ADDRESS (in either text or data space) and a STATE_POINTER which * describes the current location in the implied scan through the debug * symbols within the file which ADDRESS is within, and returns the source * line number which corresponds to ADDRESS. */ static int address_to_line(unsigned long address, struct line_debug_entry state_pointer[3]) { struct line_debug_entry *current, *next, *tmp_pointer; int use_data_symbols; current = state_pointer; next = state_pointer + 1; if (next->sym) use_data_symbols = (next->sym->nzlist.nlist.n_type & N_TYPE) == N_DATA; else return current->line; /* Go back to the beginning if we've already passed it. */ if (current->sym->nzlist.nlist.n_value > address) { tmp_pointer = init_debug_scan(use_data_symbols, (struct file_entry *) ((state_pointer + 2)->sym)); state_pointer[0] = tmp_pointer[0]; state_pointer[1] = tmp_pointer[1]; state_pointer[2] = tmp_pointer[2]; free(tmp_pointer); } /* If we're still in a bad way, return -1, meaning invalid line. */ if (current->sym->nzlist.nlist.n_value > address) return -1; while (next->sym && next->sym->nzlist.nlist.n_value <= address && next_debug_entry(use_data_symbols, state_pointer)); return current->line; } /* Macros for manipulating bitvectors. */ #define BIT_SET_P(bv, index) ((bv)[(index) >> 3] & 1 << ((index) & 0x7)) #define SET_BIT(bv, index) ((bv)[(index) >> 3] |= 1 << ((index) & 0x7)) /* * This routine will scan through the relocation data of file ENTRY, printing * out references to undefined symbols and references to symbols defined in * files with N_WARNING symbols. If DATA_SEGMENT is non-zero, it will scan * the data relocation segment (and use N_DSLINE symbols to track line * number); otherwise it will scan the text relocation segment. Warnings * will be printed on the output stream OUTFILE. Eventually, every nlist * symbol mapped through will be marked in the NLIST_BITVECTOR, so we don't * repeat ourselves when we scan the nlists themselves. */ static void do_relocation_warnings(struct file_entry *entry, int data_segment, FILE *outfile, unsigned char *nlist_bitvector) { struct relocation_info *rp, *erp; int start_of_segment; struct localsymbol *start_of_syms; struct line_debug_entry *state_pointer, *current; /* Assigned to generally static values; should not be written into. */ char *errfmt; /* * Assigned to alloca'd values cand copied into; should be freed when * done. */ char *errmsg; int invalidate_line_number; rp = data_segment ? entry->datarel : entry->textrel; erp = data_segment ? (rp + entry->ndatarel) : (rp + entry->ntextrel); start_of_syms = entry->symbols; start_of_segment = (data_segment ? entry->data_start_address : entry->text_start_address); state_pointer = init_debug_scan(data_segment != 0, entry); current = state_pointer; /* * We need to sort the relocation info here. Sheesh, so much effort * for one lousy error optimization. */ qsort(rp, erp - rp, sizeof(rp[0]), reloc_cmp); for (; rp < erp; rp++) { struct localsymbol *lsp; symbol *g; /* * If the relocation isn't resolved through a symbol, continue. */ if (!RELOC_EXTERN_P(rp)) continue; lsp = &entry->symbols[RELOC_SYMBOL(rp)]; /* * Local symbols shouldn't ever be used by relocation info, * so the next should be safe. This is, of course, wrong. * References to local BSS symbols can be the targets of * relocation info, and they can (must) be resolved through * symbols. However, these must be defined properly, (the * assembler would have caught it otherwise), so we can * ignore these cases. */ if ((g = lsp->symbol) == NULL) continue; if (!(lsp->nzlist.nz_type & N_EXT) && !SET_ELEMENT_P(lsp->nzlist.nz_type)) { warnx("internal error: `%s' N_EXT not set", g->name); continue; } errmsg = 0; if (!g->defined && !g->so_defined && list_unresolved_refs) { /* Mark as being noted by relocation warning pass. */ SET_BIT(nlist_bitvector, lsp - start_of_syms); if (g->undef_refs == 0) reported_undefineds++; if (g->undef_refs >= MAX_UREFS_PRINTED) /* Listed too many */ continue; /* Undefined symbol which we should mention */ if (++(g->undef_refs) == MAX_UREFS_PRINTED) { errfmt = "More undefined symbol %s refs follow"; invalidate_line_number = 1; } else { errfmt = "Undefined symbol `%s' referenced from %s segment"; invalidate_line_number = 0; } } else { /* Defined */ /* Potential symbol warning here */ if (!g->warning) continue; if (BIT_SET_P(nlist_bitvector, lsp - start_of_syms)) continue; /* Mark as being noted by relocation warning pass. */ SET_BIT(nlist_bitvector, lsp - start_of_syms); errfmt = 0; errmsg = g->warning; invalidate_line_number = 0; } /* If errfmt == 0, errmsg has already been defined. */ if (errfmt != 0) { char *nm; size_t len; nm = g->name; len = strlen(errfmt) + strlen(nm) + 1; errmsg = (char *) xmalloc(len); snprintf(errmsg, len, errfmt, nm, data_segment?"data":"text"); if (nm != g->name) free(nm); } address_to_line(RELOC_ADDRESS(rp) + start_of_segment, state_pointer); if (current->line >= 0) fprintf(outfile, "%s:%d: %s\n", current->filename, invalidate_line_number ? 0 : current->line, errmsg); else fprintf(outfile, "%s: %s\n", current->filename, errmsg); if (errfmt != 0) free(errmsg); } free(state_pointer); } /* * Print on OUTFILE a list of all warnings generated by references and/or * definitions in the file ENTRY. List source file and line number if * possible, just the .o file if not. */ static void do_file_warnings(struct file_entry *entry, void *arg) { int nsym; int i; char *errfmt, *file_name; int line_number; int dont_allow_symbol_name; u_char *nlist_bitvector; struct line_debug_entry *text_scan, *data_scan; FILE *outfile = arg; nsym = entry->nsymbols; nlist_bitvector = (u_char *)alloca((nsym >> 3) + 1); bzero(nlist_bitvector, (nsym >> 3) + 1); /* Read in the strings */ entry->strings = (char *)alloca(entry->string_size); read_entry_strings(file_open(entry), entry); if (!(entry->flags & E_DYNAMIC)) { /* Do text warnings based on a scan through the reloc info. */ do_relocation_warnings(entry, 0, outfile, nlist_bitvector); /* Do data warnings based on a scan through the reloc info. */ do_relocation_warnings(entry, 1, outfile, nlist_bitvector); } /* * Scan through all of the nlist entries in this file and pick up * anything that the scan through the relocation stuff didn't. */ text_scan = init_debug_scan(0, entry); data_scan = init_debug_scan(1, entry); for (i = 0; i < nsym; i++) { struct nlist *np; symbol *g; g = entry->symbols[i].symbol; np = &entry->symbols[i].nzlist.nlist; if (g == NULL) continue; if (!(np->n_type & N_EXT) && !SET_ELEMENT_P(np->n_type)) { warnx("internal error: `%s' N_EXT not set", g->name); continue; } if (!(g->flags & GS_REFERENCED)) { #if 0 /* Check for undefined shobj symbols */ struct localsymbol *lsp; int type; for (lsp = g->sorefs; lsp; lsp = lsp->next) { type = lsp->nzlist.nz_type; if ((type & N_EXT) && type != (N_UNDF | N_EXT)) { break; } } if (type == (N_UNDF | N_EXT)) { fprintf(stderr, "Undefined symbol %s referenced from %s\n", g->name, get_file_name(entry)); } #endif continue; } dont_allow_symbol_name = 0; if (list_multiple_defs && g->mult_defs) { errfmt = "Definition of symbol `%s' (multiply defined)"; switch (np->n_type) { case N_TEXT | N_EXT: line_number = address_to_line(np->n_value, text_scan); file_name = text_scan[0].filename; break; case N_DATA | N_EXT: line_number = address_to_line(np->n_value, data_scan); file_name = data_scan[0].filename; break; case N_SETA | N_EXT: case N_SETT | N_EXT: case N_SETD | N_EXT: case N_SETB | N_EXT: if (g->mult_defs == 2) continue; errfmt = "First set element definition of symbol `%s' (multiply defined)"; line_number = -1; break; case N_SIZE | N_EXT: errfmt = "Size element definition of symbol `%s' (multiply defined)"; line_number = -1; break; case N_INDR | N_EXT: errfmt = "Alias definition of symbol `%s' (multiply defined)"; line_number = -1; break; case N_UNDF | N_EXT: /* Don't print out multiple defs at references.*/ continue; default: warnx("%s: unexpected multiple definitions " "of symbol `%s', type %#x", get_file_name(entry), g->name, np->n_type); break; } } else if (BIT_SET_P(nlist_bitvector, i)) { continue; } else if (list_unresolved_refs && !g->defined && !g->so_defined) { if (g->undef_refs == 0) reported_undefineds++; if (g->undef_refs >= MAX_UREFS_PRINTED) continue; if (++(g->undef_refs) == MAX_UREFS_PRINTED) errfmt = "More undefined `%s' refs follow"; else errfmt = "Undefined symbol `%s' referenced"; line_number = -1; } else if (g->def_lsp && g->def_lsp->entry != entry && !(entry->flags & E_DYNAMIC) && g->def_lsp->entry->flags & E_SECONDCLASS) { if (g->undef_refs == 0) reported_undefineds++; if (g->undef_refs >= MAX_UREFS_PRINTED) continue; if (++(g->undef_refs) == MAX_UREFS_PRINTED) { errfmt = "More undefined `%s' refs follow"; line_number = -1; } else { fprintf(outfile, "%s: Undefined symbol `%s' referenced (use %s ?)\n", get_file_name(entry), g->name, g->def_lsp->entry->local_sym_name); continue; } } else if (g->warning) { /* * There are two cases in which we don't want to do * this. The first is if this is a definition instead * of a reference. The second is if it's the reference * used by the warning stabs itself. */ if (np->n_type != (N_EXT | N_UNDF) || (entry->symbols[i].flags & LS_WARNING)) continue; errfmt = g->warning; line_number = -1; dont_allow_symbol_name = 1; } else continue; if (line_number == -1) fprintf(outfile, "%s: ", get_file_name(entry)); else fprintf(outfile, "%s:%d: ", file_name, line_number); if (dont_allow_symbol_name) fprintf(outfile, "%s", errfmt); else fprintf(outfile, errfmt, g->name); fputc('\n', outfile); } free(text_scan); free(data_scan); entry->strings = 0; /* Since it will disappear anyway. */ } int do_warnings(FILE *outfile) { list_unresolved_refs = !relocatable_output && ( (undefined_global_sym_count - undefined_weak_sym_count) > 0 || undefined_shobj_sym_count ); list_multiple_defs = multiple_def_count != 0; if (!(list_unresolved_refs || list_warning_symbols || list_multiple_defs)) /* No need to run this routine */ return 1; if (entry_symbol && !entry_symbol->defined) fprintf(outfile, "Undefined entry symbol `%s'\n", entry_symbol->name); each_file(do_file_warnings, (void *)outfile); if (list_unresolved_refs && reported_undefineds != (undefined_global_sym_count - undefined_weak_sym_count)) warnx("internal consistency check failure: " "# undefined symbols %d, accounted for %d", (undefined_global_sym_count - undefined_weak_sym_count), reported_undefineds); if (list_unresolved_refs || list_multiple_defs) return 0; return 1; }