usr.bin/gprof/aout.c

   1 /* $DragonFly: src/usr.bin/gprof/aout.c,v 1.3 2006/01/22 03:43:37 swildner Exp $                                                                */
   2 #include <a.out.h>
   3
   4 #include "gprof.h"
   5
   6 static void getstrtab(FILE *, const char *);
   7 static void getsymtab(FILE *, const char *);
   8 static void gettextspace(FILE *);
   9 static bool funcsymbol(struct nlist *);
  10
  11 static char     *strtab;                /* string table in core */
  12 static long     ssiz;                   /* size of the string table */
  13 static struct   exec xbuf;              /* exec header of a.out */
  14
  15 /* Things which get -E excluded by default. */
  16 static char     *excludes[] = { "mcount", "__mcleanup", NULL };
  17
  18     /*
  19      * Set up string and symbol tables from a.out.
  20      *  and optionally the text space.
  21      * On return symbol table is sorted by value.
  22      *
  23      * Returns 0 on success, -1 on failure.
  24      */
  25 int
  26 aout_getnfile(const char *filename, char ***defaultEs)
  27 {
  28     FILE        *nfile;
  29     int         valcmp();
  30
  31     nfile = fopen( filename ,"r");
  32     if (nfile == NULL) {
  33         perror( filename );
  34         done();
  35     }
  36     fread(&xbuf, 1, sizeof(xbuf), nfile);
  37     if (N_BADMAG(xbuf)) {
  38         fclose(nfile);
  39         return -1;
  40     }
  41     getstrtab(nfile, filename);
  42     getsymtab(nfile, filename);
  43     gettextspace( nfile );
  44     fclose(nfile);
  45 #   ifdef DEBUG
  46         if ( debug & AOUTDEBUG ) {
  47             int j;
  48
  49             for (j = 0; j < nname; j++){
  50                 printf("[getnfile] 0X%08x\t%s\n", nl[j].value, nl[j].name);
  51             }
  52         }
  53 #   endif /* DEBUG */
  54     *defaultEs = excludes;
  55     return 0;
  56 }
  57
  58 static void
  59 getstrtab(FILE *nfile, const char *filename)
  60 {
  61
  62     fseek(nfile, (long)(N_SYMOFF(xbuf) + xbuf.a_syms), 0);
  63     if (fread(&ssiz, sizeof (ssiz), 1, nfile) == 0) {
  64         warnx("%s: no string table (old format?)" , filename );
  65         done();
  66     }
  67     strtab = calloc(ssiz, 1);
  68     if (strtab == NULL) {
  69         warnx("%s: no room for %d bytes of string table", filename , ssiz);
  70         done();
  71     }
  72     if (fread(strtab+sizeof(ssiz), ssiz-sizeof(ssiz), 1, nfile) != 1) {
  73         warnx("%s: error reading string table", filename );
  74         done();
  75     }
  76 }
  77
  78     /*
  79      * Read in symbol table
  80      */
  81 static void
  82 getsymtab(FILE *nfile, const char *filename)
  83 {
  84     long        i;
  85     int                 askfor;
  86     struct nlist        nbuf;
  87
  88     /* pass1 - count symbols */
  89     fseek(nfile, (long)N_SYMOFF(xbuf), 0);
  90     nname = 0;
  91     for (i = xbuf.a_syms; i > 0; i -= sizeof(struct nlist)) {
  92         fread(&nbuf, sizeof(nbuf), 1, nfile);
  93         if ( ! funcsymbol( &nbuf ) ) {
  94             continue;
  95         }
  96         nname++;
  97     }
  98     if (nname == 0) {
  99         warnx("%s: no symbols", filename );
 100         done();
 101     }
 102     askfor = nname + 1;
 103     nl = (nltype *) calloc( askfor , sizeof(nltype) );
 104     if (nl == 0) {
 105         warnx("no room for %d bytes of symbol table", askfor * sizeof(nltype) );
 106         done();
 107     }
 108
 109     /* pass2 - read symbols */
 110     fseek(nfile, (long)N_SYMOFF(xbuf), 0);
 111     npe = nl;
 112     nname = 0;
 113     for (i = xbuf.a_syms; i > 0; i -= sizeof(struct nlist)) {
 114         fread(&nbuf, sizeof(nbuf), 1, nfile);
 115         if ( ! funcsymbol( &nbuf ) ) {
 116 #           ifdef DEBUG
 117                 if ( debug & AOUTDEBUG ) {
 118                     printf( "[getsymtab] rejecting: 0x%x %s\n" ,
 119                             nbuf.n_type , strtab + nbuf.n_un.n_strx );
 120                 }
 121 #           endif /* DEBUG */
 122             continue;
 123         }
 124         npe->value = nbuf.n_value;
 125         npe->name = strtab+nbuf.n_un.n_strx;
 126 #       ifdef DEBUG
 127             if ( debug & AOUTDEBUG ) {
 128                 printf( "[getsymtab] %d %s 0x%08x\n" ,
 129                         nname , npe -> name , npe -> value );
 130             }
 131 #       endif /* DEBUG */
 132         npe++;
 133         nname++;
 134     }
 135     npe->value = -1;
 136 }
 137
 138     /*
 139      *  read in the text space of an a.out file
 140      */
 141 static void
 142 gettextspace(FILE *nfile)
 143 {
 144
 145     if ( cflag == 0 ) {
 146         return;
 147     }
 148     textspace = (u_char *) malloc( xbuf.a_text );
 149     if ( textspace == 0 ) {
 150         warnx("ran out room for %d bytes of text space: can't do -c" ,
 151                   xbuf.a_text );
 152         return;
 153     }
 154     (void) fseek( nfile , N_TXTOFF( xbuf ) , 0 );
 155     if ( fread( textspace , 1 , xbuf.a_text , nfile ) != xbuf.a_text ) {
 156         warnx("couldn't read text space: can't do -c");
 157         free( textspace );
 158         textspace = 0;
 159         return;
 160     }
 161 }
 162
 163 static bool
 164 funcsymbol(struct nlist *nlistp)
 165 {
 166     char        *name, c;
 167
 168         /*
 169          *      must be a text symbol,
 170          *      and static text symbols don't qualify if aflag set.
 171          */
 172     if ( ! (  ( nlistp -> n_type == ( N_TEXT | N_EXT ) )
 173            || ( ( nlistp -> n_type == N_TEXT ) && ( aflag == 0 ) ) ) ) {
 174         return FALSE;
 175     }
 176         /*
 177          *      name must start with an underscore if uflag is set.
 178          *      can't have any `funny' characters in name,
 179          *      where `funny' means `.' (.o file names)
 180          *      need to make an exception for sparc .mul & co.
 181          *      perhaps we should just drop this code entirely...
 182          */
 183     name = strtab + nlistp -> n_un.n_strx;
 184     if ( uflag && *name != '_' )
 185         return FALSE;
 186 #ifdef sparc
 187     if ( *name == '.' ) {
 188         char *p = name + 1;
 189         if ( *p == 'u' )
 190             p++;
 191         if ( strcmp ( p, "mul" ) == 0 || strcmp ( p, "div" ) == 0 ||
 192              strcmp ( p, "rem" ) == 0 )
 193                 return TRUE;
 194     }
 195 #endif
 196     while ( c = *name++ ) {
 197         if ( c == '.' ) {
 198             return FALSE;
 199         }
 200     }
 201     return TRUE;
 202 }