summaryrefslogtreecommitdiffstats
path: root/qemu/roms/ipxe/src/util/iccfix.c
blob: 528bf4b26c09c6b39e949204e73699e6923c1480 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
#include <stdint.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <elf.h>
#include <ipxe/tables.h>

#define DEBUG 0

#define eprintf(...) fprintf ( stderr, __VA_ARGS__ )

#define dprintf(...) do {						\
	if ( DEBUG )							\
		fprintf ( stderr, __VA_ARGS__ );			\
	} while ( 0 )

#ifdef SELF_INCLUDED

/**
 * Fix up ICC alignments
 *
 * @v elf		ELF header
 * @ret rc		Return status code
 *
 * See comments in tables.h for an explanation of why this monstrosity
 * is necessary.
 */
static int ICCFIX ( void *elf ) {
	ELF_EHDR *ehdr = elf;
	ELF_SHDR *shdr = ( elf + ehdr->e_shoff );
	size_t shentsize = ehdr->e_shentsize;
	unsigned int shnum = ehdr->e_shnum;
	ELF_SHDR *strtab = ( ( ( void * ) shdr ) +
			     ( ehdr->e_shstrndx * shentsize ) );
	char *strings = ( elf + strtab->sh_offset );

	for ( ; shnum-- ; shdr = ( ( ( void * ) shdr ) + shentsize ) ) {
		char *name = ( strings + shdr->sh_name );
		unsigned long align = shdr->sh_addralign;
		unsigned long new_align;

		if ( ( strncmp ( name, ".tbl.", 5 ) == 0 ) &&
		     ( align >= ICC_ALIGN_HACK_FACTOR ) ) {
			new_align = ( align / ICC_ALIGN_HACK_FACTOR );
			shdr->sh_addralign = new_align;
			dprintf ( "Section \"%s\": alignment %ld->%ld\n",
				  name, align, new_align );
		}
	}
	return 0;
}

#else /* SELF_INCLUDED */

#define SELF_INCLUDED

/* Include iccfix32() function */
#define ELF_EHDR Elf32_Ehdr
#define ELF_SHDR Elf32_Shdr
#define ICCFIX iccfix32
#include "iccfix.c"
#undef ELF_EHDR
#undef ELF_SHDR
#undef ICCFIX

/* Include iccfix64() function */
#define ELF_EHDR Elf64_Ehdr
#define ELF_SHDR Elf64_Shdr
#define ICCFIX iccfix64
#include "iccfix.c"
#undef ELF_EHDR
#undef ELF_SHDR
#undef ICCFIX

static int iccfix ( const char *filename ) {
	int fd;
	struct stat stat;
	void *elf;
	unsigned char *eident;
	int rc;

	/* Open and mmap file */
	fd = open ( filename, O_RDWR );
	if ( fd < 0 ) {
		eprintf ( "Could not open %s: %s\n",
			  filename, strerror ( errno ) );
		rc = -1;
		goto err_open;
	}
	if ( fstat ( fd, &stat ) < 0 ) {
		eprintf ( "Could not determine size of %s: %s\n",
			  filename, strerror ( errno ) );
		rc = -1;
		goto err_fstat;
	}
	elf = mmap ( NULL, stat.st_size, ( PROT_READ | PROT_WRITE ),
		     MAP_SHARED, fd, 0 );
	if ( elf == MAP_FAILED ) {
		eprintf ( "Could not map %s: %s\n",
			  filename, strerror ( errno ) );
		rc = -1;
		goto err_mmap;
	}

	/* Perform fixups */
	eident = elf;
	switch ( eident[EI_CLASS] ) {
	case ELFCLASS32:
		rc = iccfix32 ( elf );
		break;
	case ELFCLASS64:
		rc = iccfix64 ( elf );
		break;
	default:
		eprintf ( "Unknown ELF class %d in %s\n",
			  eident[EI_CLASS], filename );
		rc = -1;
		break;
	}

	munmap ( elf, stat.st_size );
 err_mmap:
 err_fstat:
	close ( fd );
 err_open:
	return rc;
}

int main ( int argc, char **argv ) {
	int i;
	int rc;

	/* Parse command line */
	if ( argc < 2 ) {
		eprintf ( "Syntax: %s <object_file>...\n", argv[0] );
		exit ( 1 );
	}

	/* Process each object in turn */
	for ( i = 1 ; i < argc ; i++ ) {
		if ( ( rc = iccfix ( argv[i] ) ) != 0 ) {
			eprintf ( "Could not fix up %s\n", argv[i] );
			exit ( 1 );
		}
	}

	return 0;
}

#endif /* SELF_INCLUDED */