nasm-elf-visibility-r2.patch

   1 Add support for declaring elf visibility attributes.  Used to
   2 help cleanup TEXTRELs in misc libraries (like libsdl).
   3
   4 Syntax to declare function foo hidden:
   5 GLOBAL foo:function hidden
   6
   7 Patch by Mike Frysinger <vapier@gentoo.org>
   8
   9 http://sourceforge.net/mailarchive/forum.php?thread_id=9230919&forum_id=4978
  10
  11 --- nasm/output/outelf.c
  12 +++ nasm/output/outelf.c
  13 @@ -50,6 +50,7 @@ struct Symbol {
  14      long strpos;                /* string table position of name */
  15      long section;               /* section ID of the symbol */
  16      int type;                   /* symbol type */
  17 +    int other;                  /* symbol visibility */
  18      long value;                 /* address, or COMMON variable align */
  19      long size;                  /* size of symbol */
  20      long globnum;               /* symbol table offset if global */
  21 @@ -113,9 +114,15 @@ extern struct ofmt of_elf;
  22
  23  #define SYM_SECTION 0x04
  24  #define SYM_GLOBAL 0x10
  25 +#define SYM_NOTYPE 0x00
  26  #define SYM_DATA 0x01
  27  #define SYM_FUNCTION 0x02
  28
  29 +#define STV_DEFAULT 0
  30 +#define STV_INTERNAL 1
  31 +#define STV_HIDDEN 2
  32 +#define STV_PROTECTED 3
  33 +
  34  #define GLOBAL_TEMP_BASE 16     /* bigger than any constant sym id */
  35
  36  #define SEG_ALIGN 16            /* alignment of sections in file */
  37 @@ -493,6 +500,7 @@ static void elf_deflabel(char *name, lon
  38
  39      sym->strpos = pos;
  40      sym->type = is_global ? SYM_GLOBAL : 0;
  41 +    sym->other = STV_DEFAULT;
  42      sym->size = 0;
  43      if (segment == NO_SEG)
  44          sym->section = SHN_ABS;
  45 @@ -570,18 +578,39 @@ static void elf_deflabel(char *name, lon
  46              sym->next = sects[sym->section - 1]->gsyms;
  47              sects[sym->section - 1]->gsyms = sym;
  48
  49 +            /* ELF syntax: GLOBAL name[:type [visibility]] */
  50              if (special) {
  51 -                int n = strcspn(special, " ");
  52 -
  53 +                int n = strcspn(special, " \t");
  54                  if (!nasm_strnicmp(special, "function", n))
  55                      sym->type |= SYM_FUNCTION;
  56                  else if (!nasm_strnicmp(special, "data", n) ||
  57                           !nasm_strnicmp(special, "object", n))
  58                      sym->type |= SYM_DATA;
  59 +                else if (!nasm_strnicmp(special, "notype", n))
  60 +                    sym->type |= SYM_NOTYPE;
  61                  else
  62                      error(ERR_NONFATAL, "unrecognised symbol type `%.*s'",
  63                            n, special);
  64 +                special += n;
  65 +
  66 +                while (isspace(*special))
  67 +                    ++special;
  68 +                if (*special) {
  69 +                    n = strcspn(special, " \t");
  70 +                    if (!nasm_strnicmp(special, "default", n))
  71 +                        sym->other = STV_DEFAULT;
  72 +                    else if (!nasm_strnicmp(special, "internal", n))
  73 +                        sym->other = STV_INTERNAL;
  74 +                    else if (!nasm_strnicmp(special, "hidden", n))
  75 +                        sym->other = STV_HIDDEN;
  76 +                    else if (!nasm_strnicmp(special, "protected", n))
  77 +                        sym->other = STV_PROTECTED;
  78 +                    else
  79 +                        n = 0;
  80 +                    special += n;
  81 +                }
  82 +
  83 -                if (special[n]) {
  84 +                if (*special) {
  85                      struct tokenval tokval;
  86                      expr *e;
  87                      int fwd = FALSE;
  88 @@ -1120,7 +1149,8 @@ static struct SAA *elf_build_symtab(long
  89          WRITELONG(p, sym->strpos);
  90          WRITELONG(p, sym->value);
  91          WRITELONG(p, sym->size);
  92 -        WRITESHORT(p, sym->type);       /* local non-typed thing */
  93 +        WRITECHAR(p, sym->type);       /* local non-typed thing */
  94 +        WRITECHAR(p, sym->other);
  95          WRITESHORT(p, sym->section);
  96          saa_wbytes(s, entry, 16L);
  97          *len += 16;
  98 @@ -1138,7 +1168,8 @@ static struct SAA *elf_build_symtab(long
  99          WRITELONG(p, sym->strpos);
 100          WRITELONG(p, sym->value);
 101          WRITELONG(p, sym->size);
 102 -        WRITESHORT(p, sym->type);       /* global non-typed thing */
 103 +        WRITECHAR(p, sym->type);       /* global non-typed thing */
 104 +        WRITECHAR(p, sym->other);
 105          WRITESHORT(p, sym->section);
 106          saa_wbytes(s, entry, 16L);
 107          *len += 16;