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-rw-r--r--sys/src/cmd/python/Python/mysnprintf.c93
1 files changed, 0 insertions, 93 deletions
diff --git a/sys/src/cmd/python/Python/mysnprintf.c b/sys/src/cmd/python/Python/mysnprintf.c
deleted file mode 100644
index 4d3770d89..000000000
--- a/sys/src/cmd/python/Python/mysnprintf.c
+++ /dev/null
@@ -1,93 +0,0 @@
-#include "Python.h"
-#include <ctype.h>
-
-/* snprintf() wrappers. If the platform has vsnprintf, we use it, else we
- emulate it in a half-hearted way. Even if the platform has it, we wrap
- it because platforms differ in what vsnprintf does in case the buffer
- is too small: C99 behavior is to return the number of characters that
- would have been written had the buffer not been too small, and to set
- the last byte of the buffer to \0. At least MS _vsnprintf returns a
- negative value instead, and fills the entire buffer with non-\0 data.
-
- The wrappers ensure that str[size-1] is always \0 upon return.
-
- PyOS_snprintf and PyOS_vsnprintf never write more than size bytes
- (including the trailing '\0') into str.
-
- If the platform doesn't have vsnprintf, and the buffer size needed to
- avoid truncation exceeds size by more than 512, Python aborts with a
- Py_FatalError.
-
- Return value (rv):
-
- When 0 <= rv < size, the output conversion was unexceptional, and
- rv characters were written to str (excluding a trailing \0 byte at
- str[rv]).
-
- When rv >= size, output conversion was truncated, and a buffer of
- size rv+1 would have been needed to avoid truncation. str[size-1]
- is \0 in this case.
-
- When rv < 0, "something bad happened". str[size-1] is \0 in this
- case too, but the rest of str is unreliable. It could be that
- an error in format codes was detected by libc, or on platforms
- with a non-C99 vsnprintf simply that the buffer wasn't big enough
- to avoid truncation, or on platforms without any vsnprintf that
- PyMem_Malloc couldn't obtain space for a temp buffer.
-
- CAUTION: Unlike C99, str != NULL and size > 0 are required.
-*/
-
-int
-PyOS_snprintf(char *str, size_t size, const char *format, ...)
-{
- int rc;
- va_list va;
-
- va_start(va, format);
- rc = PyOS_vsnprintf(str, size, format, va);
- va_end(va);
- return rc;
-}
-
-int
-PyOS_vsnprintf(char *str, size_t size, const char *format, va_list va)
-{
- int len; /* # bytes written, excluding \0 */
-#ifndef HAVE_SNPRINTF
- char *buffer;
-#endif
- assert(str != NULL);
- assert(size > 0);
- assert(format != NULL);
-
-#ifdef HAVE_SNPRINTF
- len = vsnprintf(str, size, format, va);
-#else
- /* Emulate it. */
- buffer = PyMem_MALLOC(size + 512);
- if (buffer == NULL) {
- len = -666;
- goto Done;
- }
-
- len = vsprintf(buffer, format, va);
- if (len < 0)
- /* ignore the error */;
-
- else if ((size_t)len >= size + 512)
- Py_FatalError("Buffer overflow in PyOS_snprintf/PyOS_vsnprintf");
-
- else {
- const size_t to_copy = (size_t)len < size ?
- (size_t)len : size - 1;
- assert(to_copy < size);
- memcpy(str, buffer, to_copy);
- str[to_copy] = '\0';
- }
- PyMem_FREE(buffer);
-Done:
-#endif
- str[size-1] = '\0';
- return len;
-}