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
|
/* See LICENSE file for copyright and license details. */
#include "common.h"
static const char *const default_makefiles[] = {
"makefile",
"Makefile"
};
int
open_default_makefile(const char **pathp)
{
int fd;
size_t i;
/* The specification says that the alternatives “shall be
* tried”, but it uses the phrase “if neither … are found”,
* implying that make(1) shall fail if a file cannot be
* opened and only try the next alternative if it failed
* becomes the file does not exist.
*/
for (i = 0; i < ELEMSOF(default_makefiles); i++) {
*pathp = default_makefiles[i];
fd = open(*pathp, O_RDONLY);
if (fd >= 0) {
printinfof(WC_MAKEFILE, "found standard makefile to use: %s", *pathp);
goto find_existing_fallbacks;
} else if (errno != ENOENT) {
eprintf("found standard makefile to use, but failed to open: %s:", *pathp);
}
}
printerrorf("couldn't find any makefile to use, portable "
"alternatives are ./makefile and ./Makefile");
find_existing_fallbacks:
/* This serves two purposes: to inform the user that
* we are only checking one of the files, and which
* would (which is printed earlier), and to information
* the user that it can be confusing. It is not common
* practice run make(1) to generate ./makefile from
* ./Makefile and (either immediately or by running
* make(1) again) built the project from ./Makefile,
* although that certainly can be useful if there are
* parts of the makefile you want to generate, such
* as .h file dependencies for .c files in very large
* projects that have many .h files and many .c files
* that each only depend on a few .h files.
*/
for (i++; i < ELEMSOF(default_makefiles); i++)
if (!access(default_makefiles[i], F_OK))
warnf_confusing(WC_EXTRA_MAKEFILE,
"found additional standard makefile, this be confusing: %s",
default_makefiles[i]);
return fd;
}
void
cmdline_opt_f(const char *arg, const char **makefile_pathp)
{
static int warning_emitted = 0;
if (*makefile_pathp && !warning_emitted) {
warning_emitted = 1;
warnf_unspecified(WC_CMDLINE, "the -f option has been specified multiple times, "
"they are processed in order, but the behaviour is "
"otherwise unspecified");
printinfof(WC_CMDLINE, "this implementation will use the last "
"option and discard earlier options");
}
*makefile_pathp = arg;
}
struct line *
load_makefile(const char *path, size_t *nlinesp)
{
struct line *lines;
int fd;
if (!path) {
fd = open_default_makefile(&path);
} else if (!strcmp(path, "-")) {
/* “A pathname of '-' shall denote the standard input” */
fd = dup(STDIN_FILENO);
if (fd < 0)
eprintf("dup <stdin>:");
path = "<stdin>";
} else {
fd = open(path, O_RDONLY);
if (fd < 0)
eprintf("open %s O_RDONLY:", path);
}
lines = load_text_file(fd, path, 0, nlinesp);
close(fd);
return lines;
}
|
