debugcommands: introduce actions to perform deterministic reads
"readavailable" is useful as a debugging device to see what data is
available on a pipe. But the mechanism isn't deterministic because
what's available on a pipe is highly conditional on timing, system
load, OS behavior, etc. This makes it not suitable for tests.
We introduce "ereadline," "read," and "eread" for performing
deterministic I/O operations (at least on blocking file descriptors).
We stop short of converting existing consumers of "readavailable"
in tests because we're working out race conditions and deadlocks
on Windows. But the goal is to eventually move tests away from
"readavailable" to these new APIs.
Differential Revision: https://phab.mercurial-scm.org/D2720
/*
* Utility functions
*
* Copyright (c) 2011 Yuya Nishihara <yuya@tcha.org>
*
* This software may be used and distributed according to the terms of the
* GNU General Public License version 2 or any later version.
*/
#ifndef UTIL_H_
#define UTIL_H_
#ifdef __GNUC__
#define PRINTF_FORMAT_ __attribute__((format(printf, 1, 2)))
#define UNUSED_ __attribute__((unused))
#else
#define PRINTF_FORMAT_
#define UNUSED_
#endif
void abortmsg(const char *fmt, ...) PRINTF_FORMAT_;
void abortmsgerrno(const char *fmt, ...) PRINTF_FORMAT_;
void enablecolor(void);
void enabledebugmsg(void);
void debugmsg(const char *fmt, ...) PRINTF_FORMAT_;
void fchdirx(int dirfd);
void fsetcloexec(int fd);
void *mallocx(size_t size);
void *reallocx(void *ptr, size_t size);
int runshellcmd(const char *cmd, const char *envp[], const char *cwd);
#endif /* UTIL_H_ */