git/builtin/check-attr.c
Junio C Hamano 33e8fc8740 usage: do not insist that standard input must come from a file
The synopsys text and the usage string of subcommands that read list
of things from the standard input are often shown like this:

	git gostak [--distim] < <list-of-doshes>

This is problematic in a number of ways:

 * The way to use these commands is more often to feed them the
   output from another command, not feed them from a file.

 * Manual pages outside Git, commands that operate on the data read
   from the standard input, e.g "sort", "grep", "sed", etc., are not
   described with such a "< redirection-from-file" in their synopsys
   text.  Our doing so introduces inconsistency.

 * We do not insist on where the output should go, by saying

	git gostak [--distim] < <list-of-doshes> > <output>

 * As it is our convention to enclose placeholders inside <braket>,
   the redirection operator followed by a placeholder filename
   becomes very hard to read, both in the documentation and in the
   help text.

Let's clean them all up, after making sure that the documentation
clearly describes the modes that take information from the standard
input and what kind of things are expected on the input.

[jc: stole example for fmt-merge-msg from Jonathan]

Helped-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-16 15:27:52 -07:00

187 lines
4.4 KiB
C

#include "builtin.h"
#include "cache.h"
#include "attr.h"
#include "quote.h"
#include "parse-options.h"
static int all_attrs;
static int cached_attrs;
static int stdin_paths;
static const char * const check_attr_usage[] = {
N_("git check-attr [-a | --all | <attr>...] [--] <pathname>..."),
N_("git check-attr --stdin [-z] [-a | --all | <attr>...]"),
NULL
};
static int nul_term_line;
static const struct option check_attr_options[] = {
OPT_BOOL('a', "all", &all_attrs, N_("report all attributes set on file")),
OPT_BOOL(0, "cached", &cached_attrs, N_("use .gitattributes only from the index")),
OPT_BOOL(0 , "stdin", &stdin_paths, N_("read file names from stdin")),
OPT_BOOL('z', NULL, &nul_term_line,
N_("terminate input and output records by a NUL character")),
OPT_END()
};
static void output_attr(int cnt, struct git_attr_check *check,
const char *file)
{
int j;
for (j = 0; j < cnt; j++) {
const char *value = check[j].value;
if (ATTR_TRUE(value))
value = "set";
else if (ATTR_FALSE(value))
value = "unset";
else if (ATTR_UNSET(value))
value = "unspecified";
if (nul_term_line) {
printf("%s%c" /* path */
"%s%c" /* attrname */
"%s%c" /* attrvalue */,
file, 0, git_attr_name(check[j].attr), 0, value, 0);
} else {
quote_c_style(file, NULL, stdout, 0);
printf(": %s: %s\n", git_attr_name(check[j].attr), value);
}
}
}
static void check_attr(const char *prefix, int cnt,
struct git_attr_check *check, const char *file)
{
char *full_path =
prefix_path(prefix, prefix ? strlen(prefix) : 0, file);
if (check != NULL) {
if (git_check_attr(full_path, cnt, check))
die("git_check_attr died");
output_attr(cnt, check, file);
} else {
if (git_all_attrs(full_path, &cnt, &check))
die("git_all_attrs died");
output_attr(cnt, check, file);
free(check);
}
free(full_path);
}
static void check_attr_stdin_paths(const char *prefix, int cnt,
struct git_attr_check *check)
{
struct strbuf buf, nbuf;
int line_termination = nul_term_line ? 0 : '\n';
strbuf_init(&buf, 0);
strbuf_init(&nbuf, 0);
while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
if (line_termination && buf.buf[0] == '"') {
strbuf_reset(&nbuf);
if (unquote_c_style(&nbuf, buf.buf, NULL))
die("line is badly quoted");
strbuf_swap(&buf, &nbuf);
}
check_attr(prefix, cnt, check, buf.buf);
maybe_flush_or_die(stdout, "attribute to stdout");
}
strbuf_release(&buf);
strbuf_release(&nbuf);
}
static NORETURN void error_with_usage(const char *msg)
{
error("%s", msg);
usage_with_options(check_attr_usage, check_attr_options);
}
int cmd_check_attr(int argc, const char **argv, const char *prefix)
{
struct git_attr_check *check;
int cnt, i, doubledash, filei;
if (!is_bare_repository())
setup_work_tree();
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, check_attr_options,
check_attr_usage, PARSE_OPT_KEEP_DASHDASH);
if (read_cache() < 0) {
die("invalid cache");
}
if (cached_attrs)
git_attr_set_direction(GIT_ATTR_INDEX, NULL);
doubledash = -1;
for (i = 0; doubledash < 0 && i < argc; i++) {
if (!strcmp(argv[i], "--"))
doubledash = i;
}
/* Process --all and/or attribute arguments: */
if (all_attrs) {
if (doubledash >= 1)
error_with_usage("Attributes and --all both specified");
cnt = 0;
filei = doubledash + 1;
} else if (doubledash == 0) {
error_with_usage("No attribute specified");
} else if (doubledash < 0) {
if (!argc)
error_with_usage("No attribute specified");
if (stdin_paths) {
/* Treat all arguments as attribute names. */
cnt = argc;
filei = argc;
} else {
/* Treat exactly one argument as an attribute name. */
cnt = 1;
filei = 1;
}
} else {
cnt = doubledash;
filei = doubledash + 1;
}
/* Check file argument(s): */
if (stdin_paths) {
if (filei < argc)
error_with_usage("Can't specify files with --stdin");
} else {
if (filei >= argc)
error_with_usage("No file specified");
}
if (all_attrs) {
check = NULL;
} else {
check = xcalloc(cnt, sizeof(*check));
for (i = 0; i < cnt; i++) {
const char *name;
struct git_attr *a;
name = argv[i];
a = git_attr(name);
if (!a)
return error("%s: not a valid attribute name",
name);
check[i].attr = a;
}
}
if (stdin_paths)
check_attr_stdin_paths(prefix, cnt, check);
else {
for (i = filei; i < argc; i++)
check_attr(prefix, cnt, check, argv[i]);
maybe_flush_or_die(stdout, "attribute to stdout");
}
return 0;
}