[PATCH 4/4] Cygwin: include/cygwin/limits.h: new header
Ken Brown
kbrown@cornell.edu
Fri Jan 29 19:24:21 GMT 2021
The new header defines some Cygwin-specific limits, using private
names. It is included by include/limits.h.
For example, we now have
#define __OPEN_MAX 3200
in include/cygwin/limits.h and
#define OPEN_MAX __OPEN_MAX
in include/limits.h. The purpose is to hide implementation details
from users who view <limits.h>.
---
winsup/cygwin/include/cygwin/limits.h | 65 ++++++++++++++++++++++
winsup/cygwin/include/limits.h | 80 +++++++++++----------------
2 files changed, 98 insertions(+), 47 deletions(-)
create mode 100644 winsup/cygwin/include/cygwin/limits.h
diff --git a/winsup/cygwin/include/cygwin/limits.h b/winsup/cygwin/include/cygwin/limits.h
new file mode 100644
index 000000000..f005d5742
--- /dev/null
+++ b/winsup/cygwin/include/cygwin/limits.h
@@ -0,0 +1,65 @@
+/* cygwin/limits.h
+
+This file is part of Cygwin.
+
+This software is a copyrighted work licensed under the terms of the
+Cygwin license. Please consult the file "CYGWIN_LICENSE" for
+details. */
+
+#ifndef _CYGWIN_LIMITS_H__
+#define _CYGWIN_LIMITS_H__
+
+#define __AIO_LISTIO_MAX 32
+#define __AIO_MAX 8
+#define __AIO_PRIO_DELTA_MAX 0
+
+/* 32000 is the safe value used for Windows processes when called from
+ Cygwin processes. */
+#define __ARG_MAX 32000
+#define __ATEXIT_MAX 32
+#define __CHILD_MAX 256
+#define __DELAYTIMER_MAX __INT_MAX__
+#define __HOST_NAME_MAX 255
+#define __IOV_MAX 1024
+#define __LOGIN_NAME_MAX 256 /* equal to UNLEN defined in w32api/lmcons.h */
+#define __MQ_OPEN_MAX 256
+#define __MQ_PRIO_MAX INT_MAX
+#define __OPEN_MAX 3200 /* value of the old OPEN_MAX_MAX */
+#define __PAGESIZE 65536
+#define __PTHREAD_DESTRUCTOR_ITERATIONS 4
+
+/* Tls has 1088 items - and we don't want to use them all :] */
+#define __PTHREAD_KEYS_MAX 1024
+/* Actually the minimum stack size is somewhat of a split personality.
+ The size parameter in a CreateThread call is the size of the initially
+ commited stack size, which can be specified as low as 4K. However, the
+ default *reserved* stack size is 1 Meg, unless the .def file specifies
+ another STACKSIZE value. And even if you specify a stack size below 64K,
+ the allocation granularity is in the way. You can never squeeze multiple
+ threads in the same allocation granularity slot. Oh well. */
+#define __PTHREAD_STACK_MIN 65536
+
+/* FIXME: We only support one realtime signal in 32 bit mode, but
+ _POSIX_RTSIG_MAX is 8. */
+#if __WORDSIZE == 64
+#define __RTSIG_MAX 33
+#else
+#define __RTSIG_MAX 1
+#endif
+#define __SEM_VALUE_MAX 1147483648
+#define __SIGQUEUE_MAX 32
+#define __STREAM_MAX 20
+#define __SYMLOOP_MAX 10
+#define __TIMER_MAX 32
+#define __TTY_NAME_MAX 32
+#define __FILESIZEBITS 64
+#define __LINK_MAX 1024
+#define __MAX_CANON 255
+#define __MAX_INPUT 255
+#define __NAME_MAX 255
+
+/* Keep in sync with __PATHNAME_MAX__ in cygwin/config.h */
+#define __PATH_MAX 4096
+#define __PIPE_BUF 4096
+
+#endif /* _CYGWIN_LIMITS_H__ */
diff --git a/winsup/cygwin/include/limits.h b/winsup/cygwin/include/limits.h
index 497d45419..6bdc9b40b 100644
--- a/winsup/cygwin/include/limits.h
+++ b/winsup/cygwin/include/limits.h
@@ -10,6 +10,7 @@ details. */
#include <features.h>
#include <bits/wordsize.h>
+#include <cygwin/limits.h>
#ifndef _MACH_MACHLIMITS_H_
@@ -156,67 +157,66 @@ details. */
/* Maximum number of I/O operations in a single list I/O call supported by
the implementation. */
-#define AIO_LISTIO_MAX 32
+#define AIO_LISTIO_MAX __AIO_LISTIO_MAX
/* Maximum number of outstanding asynchronous I/O operations supported by
the implementation. */
-#define AIO_MAX 8
+#define AIO_MAX __AIO_MAX
/* The maximum amount by which a process can decrease its asynchronous I/O
priority level from its own scheduling priority. Not yet implemented. */
-#define AIO_PRIO_DELTA_MAX 0
+#define AIO_PRIO_DELTA_MAX __AIO_PRIO_DELTA_MAX
/* Maximum number of bytes in arguments and environment passed in an exec
- call. 32000 is the safe value used for Windows processes when called
- from Cygwin processes. */
+ call. */
#undef ARG_MAX
-#define ARG_MAX 32000
+#define ARG_MAX __ARG_MAX
#if __XSI_VISIBLE || __POSIX_VISIBLE >= 200809
/* Maximum number of functions that may be registered with atexit(). */
#undef ATEXIT_MAX
-#define ATEXIT_MAX 32
+#define ATEXIT_MAX __ATEXIT_MAX
#endif
/* Maximum number of simultaneous processes per real user ID. */
#undef CHILD_MAX
-#define CHILD_MAX 256
+#define CHILD_MAX __CHILD_MAX
/* Maximum number of timer expiration overruns. Not yet implemented. */
#undef DELAYTIMER_MAX
-#define DELAYTIMER_MAX __INT_MAX__
+#define DELAYTIMER_MAX __DELAYTIMER_MAX
/* Maximum length of a host name. */
#undef HOST_NAME_MAX
-#define HOST_NAME_MAX 255
+#define HOST_NAME_MAX __HOST_NAME_MAX
#if __XSI_VISIBLE
/* Maximum number of iovcnt in a writev (an arbitrary number) */
#undef IOV_MAX
-#define IOV_MAX 1024
+#define IOV_MAX __IOV_MAX
#endif
/* Maximum number of characters in a login name. */
#undef LOGIN_NAME_MAX
-#define LOGIN_NAME_MAX 256 /* equal to UNLEN defined in w32api/lmcons.h */
+#define LOGIN_NAME_MAX __LOGIN_NAME_MAX
/* The maximum number of open message queue descriptors a process may hold. */
#undef MQ_OPEN_MAX
-#define MQ_OPEN_MAX OPEN_MAX
+#define MQ_OPEN_MAX __MQ_OPEN_MAX
/* The maximum number of message priorities supported by the implementation. */
#undef MQ_PRIO_MAX
-#define MQ_PRIO_MAX INT_MAX
+#define MQ_PRIO_MAX __MQ_PRIO_MAX
/* # of open files per process. This limit is returned by
getdtablesize(), sysconf(_SC_OPEN_MAX), and
getrlimit(RLIMIT_NOFILE). */
#undef OPEN_MAX
-#define OPEN_MAX 3200
+#define OPEN_MAX __OPEN_MAX
/* Size in bytes of a page. */
#undef PAGESIZE
-#define PAGESIZE 65536
+#define PAGESIZE __PAGESIZE
#if __XSI_VISIBLE
#undef PAGE_SIZE
#define PAGE_SIZE PAGESIZE
@@ -225,23 +225,15 @@ details. */
/* Maximum number of attempts made to destroy a thread's thread-specific
data values on thread exit. */
#undef PTHREAD_DESTRUCTOR_ITERATIONS
-#define PTHREAD_DESTRUCTOR_ITERATIONS 4
+#define PTHREAD_DESTRUCTOR_ITERATIONS __PTHREAD_DESTRUCTOR_ITERATIONS
/* Maximum number of data keys that can be created by a process. */
-/* Tls has 1088 items - and we don't want to use them all :] */
#undef PTHREAD_KEYS_MAX
-#define PTHREAD_KEYS_MAX 1024
+#define PTHREAD_KEYS_MAX __PTHREAD_KEYS_MAX
/* Minimum size in bytes of thread stack storage. */
-/* Actually the minimum stack size is somewhat of a split personality.
- The size parameter in a CreateThread call is the size of the initially
- commited stack size, which can be specified as low as 4K. However, the
- default *reserved* stack size is 1 Meg, unless the .def file specifies
- another STACKSIZE value. And even if you specify a stack size below 64K,
- the allocation granularity is in the way. You can never squeeze multiple
- threads in the same allocation granularity slot. Oh well. */
#undef PTHREAD_STACK_MIN
-#define PTHREAD_STACK_MIN 65536
+#define PTHREAD_STACK_MIN __PTHREAD_STACK_MIN
/* Maximum number of threads that can be created per process. */
/* Windows allows any arbitrary number of threads per process. */
@@ -249,14 +241,8 @@ details. */
/* #define PTHREAD_THREADS_MAX unspecified */
/* Maximum number of realtime signals reserved for application use. */
-/* FIXME: We only support one realtime signal in 32 bit mode, but
- _POSIX_RTSIG_MAX is 8. */
#undef RTSIG_MAX
-#if __WORDSIZE == 64
-#define RTSIG_MAX 33
-#else
-#define RTSIG_MAX 1
-#endif
+#define RTSIG_MAX __RTSIG_MAX
/* Maximum number of semaphores that a process may have. */
/* Windows allows any arbitrary number of semaphores per process. */
@@ -265,12 +251,12 @@ details. */
/* The maximum value a semaphore may have. */
#undef SEM_VALUE_MAX
-#define SEM_VALUE_MAX 1147483648
+#define SEM_VALUE_MAX __SEM_VALUE_MAX
/* Maximum number of queued signals that a process may send and have pending
at the receiver(s) at any time. */
#undef SIGQUEUE_MAX
-#define SIGQUEUE_MAX 32
+#define SIGQUEUE_MAX __SIGQUEUE_MAX
/* The maximum number of replenishment operations that may be simultaneously
pending for a particular sporadic server scheduler. Not implemented. */
@@ -279,15 +265,15 @@ details. */
/* Number of streams that one process can have open at one time. */
#undef STREAM_MAX
-#define STREAM_MAX 20
+#define STREAM_MAX __STREAM_MAX
/* Maximum number of nested symbolic links. */
#undef SYMLOOP_MAX
-#define SYMLOOP_MAX 10
+#define SYMLOOP_MAX __SYMLOOP_MAX
/* Maximum number of timer expiration overruns. */
#undef TIMER_MAX
-#define TIMER_MAX 32
+#define TIMER_MAX __TIMER_MAX
/* Maximum length of the trace event name. Not implemented. */
#undef TRACE_EVENT_NAME_MAX
@@ -311,7 +297,7 @@ details. */
/* Maximum number of characters in a tty name. */
#undef TTY_NAME_MAX
-#define TTY_NAME_MAX 32
+#define TTY_NAME_MAX __TTY_NAME_MAX
/* Maximum number of bytes supported for the name of a timezone (not of the TZ variable). Not implemented. */
#undef TZNAME_MAX
@@ -322,35 +308,35 @@ details. */
/* Minimum bits needed to represent the maximum size of a regular file. */
#undef FILESIZEBITS
-#define FILESIZEBITS 64
+#define FILESIZEBITS __FILESIZEBITS
/* Maximum number of hardlinks to a file. */
#undef LINK_MAX
-#define LINK_MAX 1024
+#define LINK_MAX __LINK_MAX
/* Maximum number of bytes in a terminal canonical input line. */
#undef MAX_CANON
-#define MAX_CANON 255
+#define MAX_CANON __MAX_CANON
/* Minimum number of bytes available in a terminal input queue. */
#undef MAX_INPUT
-#define MAX_INPUT 255
+#define MAX_INPUT __MAX_INPUT
/* Maximum length of a path component. */
#undef NAME_MAX
-#define NAME_MAX 255
+#define NAME_MAX __NAME_MAX
/* Maximum length of a path given to API functions including trailing NUL.
Deliberately set to the same default value as on Linux. Internal paths
may be longer. */
/* Keep in sync with __PATHNAME_MAX__ in cygwin/config.h */
#undef PATH_MAX
-#define PATH_MAX 4096
+#define PATH_MAX __PATH_MAX
/* # of bytes in a pipe buf. This is the max # of bytes which can be
written to a pipe in one atomic operation. */
#undef PIPE_BUF
-#define PIPE_BUF 4096
+#define PIPE_BUF __PIPE_BUF
/* Minimum number of bytes of storage actually allocated for any portion
of a file. Not implemented. */
--
2.30.0
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