object_file.cc revision 2 
1/*
2 * Copyright (c) 2003 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <list>
30#include <string>
31
32#include <sys/types.h>
33#include <sys/mman.h>
34#include <fcntl.h>
35#include <stdio.h>
36#include <unistd.h>
37
38#include "cprintf.hh"
39#include "ecoff.hh"
40#include "object_file.hh"
41#include "symtab.hh"
42
43using namespace std;
44
45ObjectFile::ObjectFile()
46    : descriptor(-1), data(NULL)
47{}
48
49ObjectFile::ObjectFile(string file)
50    : descriptor(-1), data(NULL)
51{ open(file); }
52
53ObjectFile::~ObjectFile()
54{ close(); }
55
56bool
57ObjectFile::open(string file_name)
58{
59    close();
60
61    name = file_name;
62
63    descriptor = ::open(name.c_str(), O_RDONLY);
64    if (descriptor < 0)
65        return false;
66
67    len = (size_t)::lseek(descriptor, 0, SEEK_END);
68
69    data = (uint8_t *)::mmap(NULL, len, PROT_READ, MAP_SHARED, descriptor, 0);
70    if (data == MAP_FAILED)
71        return false;
72
73    postOpen();
74
75    return true;
76}
77
78void
79ObjectFile::close()
80{
81    if (descriptor >= 0)
82        ::close(descriptor);
83
84    if (data)
85        ::munmap(data, len);
86}
87
88void
89EcoffObject::postOpen()
90{
91    exec = &(((EcoffExecHeader *)data)->f);
92    aout = &(((EcoffExecHeader *)data)->a);
93
94    text_off = aout->text_start;
95    data_off = aout->data_start;
96    bss_off = aout->bss_start;
97
98    text_size = aout->tsize;
99    data_size = aout->dsize;
100    bss_size = aout->bsize;
101}
102
103bool
104EcoffObject::loadGlobals(SymbolTable *symtab)
105{
106    if (!symtab)
107        return false;
108
109    if (exec->f_magic != ALPHAMAGIC) {
110        cprintf("wrong magic\n");
111        return false;
112    }
113
114    EcoffSymHeader *syms = (EcoffSymHeader *)(data + exec->f_symptr);
115    if (syms->magic != ECOFF_SYM_MAGIC) {
116        cprintf("bad symbol header magic\n");
117        exit(1);
118    }
119
120    EcoffExtSymEntry *ext_syms =
121        (EcoffExtSymEntry *)(data + syms->cbExtOffset);
122
123    char *ext_strings = (char *)(data + syms->cbSsExtOffset);
124    for (int i = 0; i < syms->iextMax; i++) {
125        EcoffSymEntry *entry = &(ext_syms[i].asym);
126        if (entry->iss != -1)
127            symtab->insert(entry->value, ext_strings + entry->iss);
128    }
129
130    return true;
131}
132
133bool
134EcoffObject::loadLocals(SymbolTable *symtab)
135{
136    if (!symtab)
137        return false;
138
139    if (exec->f_magic != ALPHAMAGIC) {
140        cprintf("wrong magic\n");
141        return false;
142    }
143
144    EcoffSymHeader *syms = (EcoffSymHeader *)(data + exec->f_symptr);
145    if (syms->magic != ECOFF_SYM_MAGIC) {
146        cprintf("bad symbol header magic\n");
147        exit(1);
148    }
149
150    EcoffSymEntry *local_syms = (EcoffSymEntry *)(data + syms->cbSymOffset);
151    char *local_strings = (char *)(data + syms->cbSsOffset);
152    EcoffFileDesc *fdesc = (EcoffFileDesc *)(data + syms->cbFdOffset);
153
154    for (int i = 0; i < syms->ifdMax; i++) {
155        EcoffSymEntry *entry =
156            (EcoffSymEntry *)(local_syms + fdesc[i].isymBase);
157        char *strings = (char *)(local_strings + fdesc[i].issBase);
158        for (int j = 0; j < fdesc[i].csym; j++) {
159            if (entry[j].st == 1 || entry[j].st == 6)
160                if (entry[j].iss != -1)
161                    symtab->insert(entry[j].value, strings + entry[j].iss);
162        }
163    }
164
165    for (int i = 0; i < syms->isymMax; i++) {
166        EcoffSymEntry *entry = &(local_syms[i]);
167        if (entry->st == 6)
168            if (entry->st == 1 || entry->st == 6)
169                symtab->insert(entry->value, local_strings + entry->iss);
170    }
171
172    return true;
173}
174