Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: 2501fea7aa3e9488af009b241b5324333646ac69 (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
158
159
160
161
162
163
164
165
166
167
168
169
170
// SPDX-License-Identifier: GPL-2.0
/*
 * "Optimize" a list of dependencies as spit out by gcc -MD
 * for the build framework.
 *
 * Original author:
 *   Copyright    2002 by Kai Germaschewski  <kai.germaschewski@gmx.de>
 *
 * This code has been borrowed from kbuild's fixdep (scripts/basic/fixdep.c),
 * Please check it for detailed explanation. This fixdep borow only the
 * base transformation of dependecies without the CONFIG mangle.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <limits.h>

char *target;
char *depfile;
char *cmdline;

static void usage(void)
{
	fprintf(stderr, "Usage: fixdep <depfile> <target> <cmdline>\n");
	exit(1);
}

/*
 * Print out the commandline prefixed with cmd_<target filename> :=
 */
static void print_cmdline(void)
{
	printf("cmd_%s := %s\n\n", target, cmdline);
}

/*
 * Important: The below generated source_foo.o and deps_foo.o variable
 * assignments are parsed not only by make, but also by the rather simple
 * parser in scripts/mod/sumversion.c.
 */
static void parse_dep_file(void *map, size_t len)
{
	char *m = map;
	char *end = m + len;
	char *p;
	char s[PATH_MAX];
	int is_target, has_target = 0;
	int saw_any_target = 0;
	int is_first_dep = 0;

	while (m < end) {
		/* Skip any "white space" */
		while (m < end && (*m == ' ' || *m == '\\' || *m == '\n'))
			m++;
		/* Find next "white space" */
		p = m;
		while (p < end && *p != ' ' && *p != '\\' && *p != '\n')
			p++;
		/* Is the token we found a target name? */
		is_target = (*(p-1) == ':');
		/* Don't write any target names into the dependency file */
		if (is_target) {
			/* The /next/ file is the first dependency */
			is_first_dep = 1;
			has_target = 1;
		} else if (has_target) {
			/* Save this token/filename */
			memcpy(s, m, p-m);
			s[p - m] = 0;

			/*
			 * Do not list the source file as dependency,
			 * so that kbuild is not confused if a .c file
			 * is rewritten into .S or vice versa. Storing
			 * it in source_* is needed for modpost to
			 * compute srcversions.
			 */
			if (is_first_dep) {
				/*
				 * If processing the concatenation of
				 * multiple dependency files, only
				 * process the first target name, which
				 * will be the original source name,
				 * and ignore any other target names,
				 * which will be intermediate temporary
				 * files.
				 */
				if (!saw_any_target) {
					saw_any_target = 1;
					printf("source_%s := %s\n\n",
						target, s);
					printf("deps_%s := \\\n",
						target);
				}
				is_first_dep = 0;
			} else
				printf("  %s \\\n", s);
		}
		/*
		 * Start searching for next token immediately after the first
		 * "whitespace" character that follows this token.
		 */
		m = p + 1;
	}

	if (!saw_any_target) {
		fprintf(stderr, "fixdep: parse error; no targets found\n");
		exit(1);
	}

	printf("\n%s: $(deps_%s)\n\n", target, target);
	printf("$(deps_%s):\n", target);
}

static void print_deps(void)
{
	struct stat st;
	int fd;
	void *map;

	fd = open(depfile, O_RDONLY);
	if (fd < 0) {
		fprintf(stderr, "fixdep: error opening depfile: ");
		perror(depfile);
		exit(2);
	}
	if (fstat(fd, &st) < 0) {
		fprintf(stderr, "fixdep: error fstat'ing depfile: ");
		perror(depfile);
		exit(2);
	}
	if (st.st_size == 0) {
		fprintf(stderr, "fixdep: %s is empty\n", depfile);
		close(fd);
		return;
	}
	map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
	if ((long) map == -1) {
		perror("fixdep: mmap");
		close(fd);
		return;
	}

	parse_dep_file(map, st.st_size);

	munmap(map, st.st_size);

	close(fd);
}

int main(int argc, char **argv)
{
	if (argc != 4)
		usage();

	depfile = argv[1];
	target  = argv[2];
	cmdline = argv[3];

	print_cmdline();
	print_deps();

	return 0;
}