Revision aba91192ae39cd1a2f79e7ed91e966df3cfe10b7 authored by Carlos Rica on 09 September 2007, 00:39:29 UTC, committed by Junio C Hamano on 10 September 2007, 04:30:54 UTC
Most of this patch code and message was written by Shawn O. Pearce.
I made some tests to know what the problem was, and then I changed
the code related with the SIGPIPE signal.

If the user has misconfigured `user.signingkey` in their .git/config
or just doesn't have any secret keys on their keyring and they ask
for a signed tag with `git tag -s` we better make sure the resulting
tag was actually signed by gpg.

Prior versions of builtin git-tag allowed this failure to slip
by without error as they were not checking the return value of
the finish_command() so they did not notice when gpg exited with
an error exit status.  They also did not fail if gpg produced an
empty output or if read_in_full received an error from the read
system call while trying to read the pipe back from gpg.

Finally, we did not actually honor any return value from the do_sign
function as it returns ssize_t but was being stored into an unsigned
long.  This caused the compiler to optimize out the die condition,
allowing git-tag to continue along and create the tag object.

However, when gpg gets a wrong username, it exits before any read was done
and then the writing process receives SIGPIPE and program is terminated.
By ignoring this signal, anyway, the function write_or_die gets EPIPE from
write_in_full and exits returning 0 to the system without a message.
Here we better call to write_in_full directly so we can fail
printing a message and return safely to the caller.

With these issues fixed `git-tag -s` will now fail to create the
tag and will report a non-zero exit status to its caller, thereby
allowing automated helper scripts to detect (and recover from)
failure if gpg is not working properly.

Proposed-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Carlos Rica <jasampler@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 7b02b85
Raw File
usage.c
/*
 * GIT - The information manager from hell
 *
 * Copyright (C) Linus Torvalds, 2005
 */
#include "git-compat-util.h"

static void report(const char *prefix, const char *err, va_list params)
{
	fputs(prefix, stderr);
	vfprintf(stderr, err, params);
	fputs("\n", stderr);
}

static NORETURN void usage_builtin(const char *err)
{
	fprintf(stderr, "usage: %s\n", err);
	exit(129);
}

static NORETURN void die_builtin(const char *err, va_list params)
{
	report("fatal: ", err, params);
	exit(128);
}

static void error_builtin(const char *err, va_list params)
{
	report("error: ", err, params);
}

static void warn_builtin(const char *warn, va_list params)
{
	report("warning: ", warn, params);
}

/* If we are in a dlopen()ed .so write to a global variable would segfault
 * (ugh), so keep things static. */
static void (*usage_routine)(const char *err) NORETURN = usage_builtin;
static void (*die_routine)(const char *err, va_list params) NORETURN = die_builtin;
static void (*error_routine)(const char *err, va_list params) = error_builtin;
static void (*warn_routine)(const char *err, va_list params) = warn_builtin;

void set_usage_routine(void (*routine)(const char *err) NORETURN)
{
	usage_routine = routine;
}

void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN)
{
	die_routine = routine;
}

void set_error_routine(void (*routine)(const char *err, va_list params))
{
	error_routine = routine;
}

void set_warn_routine(void (*routine)(const char *warn, va_list params))
{
	warn_routine = routine;
}


void usage(const char *err)
{
	usage_routine(err);
}

void die(const char *err, ...)
{
	va_list params;

	va_start(params, err);
	die_routine(err, params);
	va_end(params);
}

int error(const char *err, ...)
{
	va_list params;

	va_start(params, err);
	error_routine(err, params);
	va_end(params);
	return -1;
}

void warning(const char *warn, ...)
{
	va_list params;

	va_start(params, warn);
	warn_routine(warn, params);
	va_end(params);
}
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