aboutsummaryrefslogtreecommitdiff
path: root/builtin/hash-object.c
blob: 9028e1fdccea2ad44a76792adc6e335fb44cfb5c (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
/*
 * GIT - The information manager from hell
 *
 * Copyright (C) Linus Torvalds, 2005
 * Copyright (C) Junio C Hamano, 2005
 */
#include "builtin.h"
#include "blob.h"
#include "quote.h"
#include "parse-options.h"
#include "exec_cmd.h"

/*
 * This is to create corrupt objects for debugging and as such it
 * needs to bypass the data conversion performed by, and the type
 * limitation imposed by, index_fd() and its callees.
 */
static int hash_literally(unsigned char *sha1, int fd, const char *type, unsigned flags)
{
	struct strbuf buf = STRBUF_INIT;
	int ret;

	if (strbuf_read(&buf, fd, 4096) < 0)
		ret = -1;
	else
		ret = hash_sha1_file_literally(buf.buf, buf.len, type, sha1, flags);
	strbuf_release(&buf);
	return ret;
}

static void hash_fd(int fd, const char *type, const char *path, unsigned flags,
		    int literally)
{
	struct stat st;
	unsigned char sha1[20];

	if (fstat(fd, &st) < 0 ||
	    (literally
	     ? hash_literally(sha1, fd, type, flags)
	     : index_fd(sha1, fd, &st, type_from_string(type), path, flags)))
		die((flags & HASH_WRITE_OBJECT)
		    ? "Unable to add %s to database"
		    : "Unable to hash %s", path);
	printf("%s\n", sha1_to_hex(sha1));
	maybe_flush_or_die(stdout, "hash to stdout");
}

static void hash_object(const char *path, const char *type, const char *vpath,
			unsigned flags, int literally)
{
	int fd;
	fd = open(path, O_RDONLY);
	if (fd < 0)
		die_errno("Cannot open '%s'", path);
	hash_fd(fd, type, vpath, flags, literally);
}

static void hash_stdin_paths(const char *type, int no_filters, unsigned flags,
			     int literally)
{
	struct strbuf buf = STRBUF_INIT;
	struct strbuf unquoted = STRBUF_INIT;

	while (strbuf_getline(&buf, stdin) != EOF) {
		if (buf.buf[0] == '"') {
			strbuf_reset(&unquoted);
			if (unquote_c_style(&unquoted, buf.buf, NULL))
				die("line is badly quoted");
			strbuf_swap(&buf, &unquoted);
		}
		hash_object(buf.buf, type, no_filters ? NULL : buf.buf, flags,
			    literally);
	}
	strbuf_release(&buf);
	strbuf_release(&unquoted);
}

int cmd_hash_object(int argc, const char **argv, const char *prefix)
{
	static const char * const hash_object_usage[] = {
		N_("git hash-object [-t <type>] [-w] [--path=<file> | --no-filters] [--stdin] [--] <file>..."),
		N_("git hash-object  --stdin-paths"),
		NULL
	};
	const char *type = blob_type;
	int hashstdin = 0;
	int stdin_paths = 0;
	int no_filters = 0;
	int literally = 0;
	int nongit = 0;
	unsigned flags = HASH_FORMAT_CHECK;
	const char *vpath = NULL;
	const struct option hash_object_options[] = {
		OPT_STRING('t', NULL, &type, N_("type"), N_("object type")),
		OPT_BIT('w', NULL, &flags, N_("write the object into the object database"),
			HASH_WRITE_OBJECT),
		OPT_COUNTUP( 0 , "stdin", &hashstdin, N_("read the object from stdin")),
		OPT_BOOL( 0 , "stdin-paths", &stdin_paths, N_("read file names from stdin")),
		OPT_BOOL( 0 , "no-filters", &no_filters, N_("store file as is without filters")),
		OPT_BOOL( 0, "literally", &literally, N_("just hash any random garbage to create corrupt objects for debugging Git")),
		OPT_STRING( 0 , "path", &vpath, N_("file"), N_("process file as it were from this path")),
		OPT_END()
	};
	int i;
	int prefix_length = -1;
	const char *errstr = NULL;

	argc = parse_options(argc, argv, NULL, hash_object_options,
			     hash_object_usage, 0);

	if (flags & HASH_WRITE_OBJECT)
		prefix = setup_git_directory();
	else
		prefix = setup_git_directory_gently(&nongit);

	prefix_length = prefix ? strlen(prefix) : 0;
	if (vpath && prefix)
		vpath = prefix_filename(prefix, prefix_length, vpath);

	git_config(git_default_config, NULL);

	if (stdin_paths) {
		if (hashstdin)
			errstr = "Can't use --stdin-paths with --stdin";
		else if (argc)
			errstr = "Can't specify files with --stdin-paths";
		else if (vpath)
			errstr = "Can't use --stdin-paths with --path";
	}
	else {
		if (hashstdin > 1)
			errstr = "Multiple --stdin arguments are not supported";
		if (vpath && no_filters)
			errstr = "Can't use --path with --no-filters";
	}

	if (errstr) {
		error("%s", errstr);
		usage_with_options(hash_object_usage, hash_object_options);
	}

	if (hashstdin)
		hash_fd(0, type, vpath, flags, literally);

	for (i = 0 ; i < argc; i++) {
		const char *arg = argv[i];

		if (0 <= prefix_length)
			arg = prefix_filename(prefix, prefix_length, arg);
		hash_object(arg, type, no_filters ? NULL : vpath ? vpath : arg,
			    flags, literally);
	}

	if (stdin_paths)
		hash_stdin_paths(type, no_filters, flags, literally);

	return 0;
}