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* Update copyright dates with scripts/update-copyrightsPaul Eggert2024-01-011-1/+1
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* Update copyright dates with scripts/update-copyrightsJoseph Myers2023-01-061-1/+1
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* libio: Convert __obstack_vprintf_internal to buffers (bug 27124)Florian Weimer2022-12-191-0/+4
| | | | | | This fixes bug 27124 because the problematic built-in vtable is gone. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* libio: Convert __vdprintf_internal to buffersFlorian Weimer2022-12-191-0/+4
| | | | | | | | | The internal buffer size is set to 2048 bytes. This is less than the original BUFSIZ value used by buffered_vfprintf before the conversion, but it hopefully covers all cases where write boundaries matter. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* libio: Convert __vasprintf_internal to buffersFlorian Weimer2022-12-191-0/+4
| | | | | | | | | | The buffer resizing algorithm is slightly different. The initial buffer is on the stack, and small buffers are directly allocated on the heap using the exact required size. The overhead of the additional copy is compensated by the lowered setup cost for buffers compared to libio streams. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* libio: Convert __vsprintf_internal to buffersFlorian Weimer2022-12-191-0/+4
| | | | Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* stdio-common: Convert vfprintf and related functions to buffersFlorian Weimer2022-12-191-0/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vfprintf is entangled with vfwprintf (of course), __printf_fp, __printf_fphex, __vstrfmon_l_internal, and the strfrom family of functions. The latter use the internal snprintf functionality, so vsnprintf is converted as well. The simples conversion is __printf_fphex, followed by __vstrfmon_l_internal and __printf_fp, and finally __vfprintf_internal and __vfwprintf_internal. __vsnprintf_internal and strfrom* are mostly consuming the new interfaces, so they are comparatively simple. __printf_fp is a public symbol, so the FILE *-based interface had to preserved. The __printf_fp rewrite does not change the actual binary-to-decimal conversion algorithm, and digits are still not emitted directly to the target buffer. However, the staging buffer now uses bytes instead of wide characters, and one buffer copy is eliminated. The changes are at least performance-neutral in my testing. Floating point printing and snprintf improved measurably, so that this Lua script for i=1,5000000 do print(i, i * math.pi) end runs about 5% faster for me. To preserve fprintf performance for a simple "%d" format, this commit has some logic changes under LABEL (unsigned_number) to avoid additional function calls. There are certainly some very easy performance improvements here: binary, octal and hexadecimal formatting can easily avoid the temporary work buffer (the number of digits can be computed ahead-of-time using one of the __builtin_clz* built-ins). Decimal formatting can use a specialized version of _itoa_word for base 10. The existing (inconsistent) width handling between strfmon and printf is preserved here. __print_fp_buffer_1 would have to use __translated_number_width to achieve ISO conformance for printf. Test expectations in libio/tst-vtables-common.c are adjusted because the internal staging buffer merges all virtual function calls into one. In general, stack buffer usage is greatly reduced, particularly for unbuffered input streams. __printf_fp can still use a large buffer in binary128 mode for %g, though. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* stdio-common: Introduce buffers for implementing printfFlorian Weimer2022-12-191-0/+42
These buffers will eventually be used instead of FILE * objects to implement printf functions. The multibyte buffer is struct __printf_buffer, the wide buffer is struct __wprintf_buffer. To enable writing type-generic code, the header files printf_buffer-char.h and printf_buffer-wchar_t.h define the Xprintf macro differently, enabling Xprintf (buffer) to stand for __printf_buffer and __wprintf_buffer as appropriate. For common cases, macros like Xprintf_buffer are provided as a more syntactically convenient shortcut. Buffer-specific flush callbacks are implemented with a switch statement instead of a function pointer, to avoid hardening issues similar to those of libio vtables. struct __printf_buffer_as_file is needed to support custom printf specifiers because the public interface for that requires passing a FILE *, which is why there is a trapdoor back from these buffers to FILE * streams. Since the immediate user of these interfaces knows when processing has finished, there is no flush callback for the end of processing, only a flush callback for the intermediate buffer flush. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>