cpython-lru_cache-weakref: Python/mysnprintf.c annotate

annotate Python/mysnprintf.c @ 33940:dfd07b7be407 legacy-trunk

SF bug 1061968: threads: segfault or Py_FatalError at exit PyGILState_Ensure(): The fix in 2.4a3 for bug 1010677 reintroduced thread shutdown race bug 225673. Repaired by (once again) ensuring the GIL is held whenever deleting a thread state. Alas, there's no useful test case for this shy bug. Four years ago, only Guido could provoke it, on his box, and today only Armin can provoke it on his box. I've never been able to provoke it (but not for lack of trying!). This is a critical fix for 2.3.5 too, since the fix for 1010677 got backported there already and so also reintroduced 225673. I don't intend to backport this fix. For whoever (if anyone) does, there are other thread fixes in 2.4 that need backporting too, and I bet they need to happen first for this patch to apply cleanly.

author	Tim Peters <tim.peters@gmail.com>
date	Mon, 08 Nov 2004 04:30:21 +0000
parents	8af86a952b2c
children	2925b568aacc a8cc8e6f0c1a

rev	line source
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	1 #include "Python.h"
79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	2 #include <ctype.h>
79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	3
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	4 /* snprintf() wrappers. If the platform has vsnprintf, we use it, else we
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	5 emulate it in a half-hearted way. Even if the platform has it, we wrap
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	6 it because platforms differ in what vsnprintf does in case the buffer
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	7 is too small: C99 behavior is to return the number of characters that
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	8 would have been written had the buffer not been too small, and to set
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	9 the last byte of the buffer to \0. At least MS _vsnprintf returns a
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	10 negative value instead, and fills the entire buffer with non-\0 data.
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	11
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	12 The wrappers ensure that str[size-1] is always \0 upon return.
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	13
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	14 PyOS_snprintf and PyOS_vsnprintf never write more than size bytes
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	15 (including the trailing '\0') into str.
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	16
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	17 If the platform doesn't have vsnprintf, and the buffer size needed to
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	18 avoid truncation exceeds size by more than 512, Python aborts with a
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	19 Py_FatalError.
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	20
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	21 Return value (rv):
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	22
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	23 When 0 <= rv < size, the output conversion was unexceptional, and
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	24 rv characters were written to str (excluding a trailing \0 byte at
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	25 str[rv]).
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	26
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	27 When rv >= size, output conversion was truncated, and a buffer of
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	28 size rv+1 would have been needed to avoid truncation. str[size-1]
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	29 is \0 in this case.
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	30
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	31 When rv < 0, "something bad happened". str[size-1] is \0 in this
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	32 case too, but the rest of str is unreliable. It could be that
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	33 an error in format codes was detected by libc, or on platforms
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	34 with a non-C99 vsnprintf simply that the buffer wasn't big enough
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	35 to avoid truncation, or on platforms without any vsnprintf that
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	36 PyMem_Malloc couldn't obtain space for a temp buffer.
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	37
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	38 CAUTION: Unlike C99, str != NULL and size > 0 are required.
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	39 */
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	40
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	41 int
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	42 PyOS_snprintf(char str, size_t size, const char format, ...)
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	43 {
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	44 int rc;
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	45 va_list va;
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	46
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	47 va_start(va, format);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	48 rc = PyOS_vsnprintf(str, size, format, va);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	49 va_end(va);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	50 return rc;
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	51 }
79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	52
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	53 int
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	54 PyOS_vsnprintf(char str, size_t size, const char format, va_list va)
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	55 {
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	56 int len; /* # bytes written, excluding \0 */
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	57 #ifndef HAVE_SNPRINTF
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	58 char *buffer;
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	59 #endif
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	60 assert(str != NULL);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	61 assert(size > 0);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	62 assert(format != NULL);
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	63
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	64 #ifdef HAVE_SNPRINTF
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	65 len = vsnprintf(str, size, format, va);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	66 #else
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	67 /* Emulate it. */
21518 8af86a952b2c PyOS_vsnprintf(): Change PyMem_Malloc() call to PyMem_MALLOC() macro, Barry Warsaw <barry@python.org> parents: 21145 diff changeset	68 buffer = PyMem_MALLOC(size + 512);
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	69 if (buffer == NULL) {
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	70 len = -666;
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	71 goto Done;
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	72 }
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	73
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	74 len = vsprintf(buffer, format, va);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	75 if (len < 0)
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	76 /* ignore the error */;
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	77
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	78 else if ((size_t)len >= size + 512)
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	79 Py_FatalError("Buffer overflow in PyOS_snprintf/PyOS_vsnprintf");
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	80
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	81 else {
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	82 const size_t to_copy = (size_t)len < size ?
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	83 (size_t)len : size - 1;
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	84 assert(to_copy < size);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	85 memcpy(str, buffer, to_copy);
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	86 str[to_copy] = '\0';
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	87 }
21518 8af86a952b2c PyOS_vsnprintf(): Change PyMem_Malloc() call to PyMem_MALLOC() macro, Barry Warsaw <barry@python.org> parents: 21145 diff changeset	88 PyMem_FREE(buffer);
21145 87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	89 Done:
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	90 #endif
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	91 str[size-1] = '\0';
87fa6e9bd77e mysnprintf.c: Massive rewrite of PyOS_snprintf and PyOS_vsnprintf, to Tim Peters <tim.peters@gmail.com> parents: 21126 diff changeset	92 return len;
18908 79c676f9b34a This patch turns the Python API mismatch notice into a standard Marc-André Lemburg <mal@egenix.com> parents: diff changeset	93 }

Mercurial > cpython-lru_cache-weakref

annotate Python/mysnprintf.c @ 33940:dfd07b7be407 legacy-trunk