1 /* Create new COMMON symbol. 2 Copyright (C) 2002 Red Hat, Inc. 3 This file is part of elfutils. 4 Written by Ulrich Drepper <drepper (at) redhat.com>, 2002. 5 6 This file is free software; you can redistribute it and/or modify 7 it under the terms of either 8 9 * the GNU Lesser General Public License as published by the Free 10 Software Foundation; either version 3 of the License, or (at 11 your option) any later version 12 13 or 14 15 * the GNU General Public License as published by the Free 16 Software Foundation; either version 2 of the License, or (at 17 your option) any later version 18 19 or both in parallel, as here. 20 21 elfutils is distributed in the hope that it will be useful, but 22 WITHOUT ANY WARRANTY; without even the implied warranty of 23 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 24 General Public License for more details. 25 26 You should have received copies of the GNU General Public License and 27 the GNU Lesser General Public License along with this program. If 28 not, see <http://www.gnu.org/licenses/>. */ 29 30 #ifdef HAVE_CONFIG_H 31 # include <config.h> 32 #endif 33 34 #include <inttypes.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <string.h> 38 39 #include <libasmP.h> 40 #include <system.h> 41 42 43 /* Object for special COMMON section. */ 44 static const AsmScn_t __libasm_com_scn = 45 { 46 .data = { 47 .main = { 48 .scn = ASM_COM_SCN 49 } 50 } 51 }; 52 53 54 AsmSym_t * 55 asm_newcomsym (AsmCtx_t *ctx, const char *name, GElf_Xword size, 56 GElf_Addr align) 57 { 58 AsmSym_t *result; 59 60 if (ctx == NULL) 61 /* Something went wrong before. */ 62 return NULL; 63 64 /* Common symbols are public. Therefore the user must provide a 65 name. */ 66 if (name == NULL) 67 { 68 __libasm_seterrno (ASM_E_INVALID); 69 return NULL; 70 } 71 72 rwlock_wrlock (ctx->lock); 73 74 result = (AsmSym_t *) malloc (sizeof (AsmSym_t)); 75 if (result == NULL) 76 return NULL; 77 78 result->scn = (AsmScn_t *) &__libasm_com_scn; 79 result->size = size; 80 /* XXX Do we have to allow a different type? */ 81 result->type = STT_OBJECT; 82 /* XXX Do we have to allow a different binding? */ 83 result->binding = STB_GLOBAL; 84 result->symidx = 0; 85 result->strent = ebl_strtabadd (ctx->symbol_strtab, name, 0); 86 87 /* The value of a COM symbol is the alignment. Since there are no 88 subsection and the initial offset of the section is 0 we can get 89 the alignment recorded by storing it into the offset field. */ 90 result->offset = align; 91 92 if (unlikely (ctx->textp)) 93 fprintf (ctx->out.file, "\t.comm %s, %" PRIuMAX ", %" PRIuMAX "\n", 94 name, (uintmax_t) size, (uintmax_t) align); 95 else 96 { 97 /* Put the symbol in the hash table so that we can later find it. */ 98 if (asm_symbol_tab_insert (&ctx->symbol_tab, elf_hash (name), result) 99 != 0) 100 { 101 /* The symbol already exists. */ 102 __libasm_seterrno (ASM_E_DUPLSYM); 103 free (result); 104 result = NULL; 105 } 106 else if (name != NULL && asm_emit_symbol_p (name)) 107 /* Only count non-private symbols. */ 108 ++ctx->nsymbol_tab; 109 } 110 111 rwlock_unlock (ctx->lock); 112 113 return result; 114 } 115
