git/builtin/var.c
Jeff King 4db16f58c7 var: mark unused parameters in git_var callbacks
We abstract the set of variables into a table, with a "read" callback to
provide the value of each. Each callback takes a "flag" argument, but
most callbacks don't make use of it.

This flag is a bit odd. It may be set to IDENT_STRICT, which make sense
for ident-based callbacks, but is just confusing for things like
GIT_EDITOR.

At first glance, it seems like this is just a hack to let us directly
stick the generic git_committer_info() and git_author_info() functions
into our table. And we'd be better off to wrap them with local functions
which pass IDENT_STRICT, and have our callbacks take no option at all.

But that doesn't quite work. We pass IDENT_STRICT when the caller asks
for a specific variable, but otherwise do not (so that "git var -l" does
not bail if the committer ident cannot be formed).

So we really do need to pass in the flag to each invocation, even if the
individual callback doesn't care about it. Let's mark the unused ones so
that -Wunused-parameter does not complain. And while we're here, let's
rename them so that it's clear that the flag values we get will be from
the IDENT_* set. That may prevent confusion for future readers of the
code.

Another option would be to define our own local "strict" flag for the
callbacks, and then have wrappers that translate that to IDENT_STRICT
where it matters. But that would be more boilerplate for little gain
(most functions would still ignore the "strict" flag anyway).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: brian m. carlson <bk2204@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-27 11:31:05 -07:00

110 lines
2.0 KiB
C

/*
* GIT - The information manager from hell
*
* Copyright (C) Eric Biederman, 2005
*/
#include "builtin.h"
#include "config.h"
#include "editor.h"
#include "ident.h"
#include "pager.h"
#include "refs.h"
static const char var_usage[] = "git var (-l | <variable>)";
static const char *editor(int ident_flag UNUSED)
{
return git_editor();
}
static const char *sequence_editor(int ident_flag UNUSED)
{
return git_sequence_editor();
}
static const char *pager(int ident_flag UNUSED)
{
const char *pgm = git_pager(1);
if (!pgm)
pgm = "cat";
return pgm;
}
static const char *default_branch(int ident_flag UNUSED)
{
return git_default_branch_name(1);
}
struct git_var {
const char *name;
const char *(*read)(int);
};
static struct git_var git_vars[] = {
{ "GIT_COMMITTER_IDENT", git_committer_info },
{ "GIT_AUTHOR_IDENT", git_author_info },
{ "GIT_EDITOR", editor },
{ "GIT_SEQUENCE_EDITOR", sequence_editor },
{ "GIT_PAGER", pager },
{ "GIT_DEFAULT_BRANCH", default_branch },
{ "", NULL },
};
static void list_vars(void)
{
struct git_var *ptr;
const char *val;
for (ptr = git_vars; ptr->read; ptr++)
if ((val = ptr->read(0)))
printf("%s=%s\n", ptr->name, val);
}
static const struct git_var *get_git_var(const char *var)
{
struct git_var *ptr;
for (ptr = git_vars; ptr->read; ptr++) {
if (strcmp(var, ptr->name) == 0) {
return ptr;
}
}
return NULL;
}
static int show_config(const char *var, const char *value, void *cb)
{
if (value)
printf("%s=%s\n", var, value);
else
printf("%s\n", var);
return git_default_config(var, value, cb);
}
int cmd_var(int argc, const char **argv, const char *prefix UNUSED)
{
const struct git_var *git_var;
const char *val;
if (argc != 2)
usage(var_usage);
if (strcmp(argv[1], "-l") == 0) {
git_config(show_config, NULL);
list_vars();
return 0;
}
git_config(git_default_config, NULL);
git_var = get_git_var(argv[1]);
if (!git_var)
usage(var_usage);
val = git_var->read(IDENT_STRICT);
if (!val)
return 1;
printf("%s\n", val);
return 0;
}