📄 vsnprintf.c
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/* Copyright (C) 2004 Manuel Novoa III <mjn3@codepoet.org> * * GNU Library General Public License (LGPL) version 2 or later. * * Dedicated to Toni. See uClibc/DEDICATION.mjn3 for details. */#include "_stdio.h"#include <stdarg.h>#ifdef __UCLIBC_MJN3_ONLY__#warning WISHLIST: Implement vsnprintf for non-buffered and no custom stream case.#endif /* __UCLIBC_MJN3_ONLY__ */#ifdef __STDIO_BUFFERSint vsnprintf(char *__restrict buf, size_t size, const char * __restrict format, va_list arg){ FILE f; int rv;/* __STDIO_STREAM_RESET_GCS(&f); */#ifdef __UCLIBC_HAS_GLIBC_CUSTOM_STREAMS__ f.__cookie = &(f.__filedes); f.__gcs.read = NULL; f.__gcs.write = NULL; f.__gcs.seek = NULL; f.__gcs.close = NULL;#endif f.__filedes = __STDIO_STREAM_FAKE_VSNPRINTF_FILEDES; f.__modeflags = (__FLAG_NARROW|__FLAG_WRITEONLY|__FLAG_WRITING);#ifdef __UCLIBC_HAS_WCHAR__ f.__ungot_width[0] = 0;#endif /* __UCLIBC_HAS_WCHAR__ */#ifdef __STDIO_MBSTATE __INIT_MBSTATE(&(f.__state));#endif /* __STDIO_MBSTATE */#ifdef __UCLIBC_HAS_THREADS__ f.__user_locking = 1; /* Set user locking. */ __stdio_init_mutex(&f.__lock);#endif f.__nextopen = NULL; if (size > SIZE_MAX - (size_t) buf) { size = SIZE_MAX - (size_t) buf; } /* Set these last since __bufputc initialization depends on * __user_locking and only gets set if user locking is on. */ f.__bufstart = buf; f.__bufend = buf + size; __STDIO_STREAM_INIT_BUFREAD_BUFPOS(&f); __STDIO_STREAM_DISABLE_GETC(&f); __STDIO_STREAM_ENABLE_PUTC(&f); rv = vfprintf(&f, format, arg); if (size) { if (f.__bufpos == f.__bufend) { --f.__bufpos; } *f.__bufpos = 0; } return rv;}#elif defined(__USE_OLD_VFPRINTF__)typedef struct { FILE f; unsigned char *bufend; /* pointer to 1 past end of buffer */ unsigned char *bufpos;} __FILE_vsnprintf;int vsnprintf(char *__restrict buf, size_t size, const char * __restrict format, va_list arg){ __FILE_vsnprintf f; int rv; f.bufpos = buf; if (size > SIZE_MAX - (size_t) buf) { size = SIZE_MAX - (size_t) buf; } f.bufend = buf + size;/* __STDIO_STREAM_RESET_GCS(&f.f); */#ifdef __UCLIBC_HAS_GLIBC_CUSTOM_STREAMS__ f.f.__cookie = &(f.f.__filedes); f.f.__gcs.read = NULL; f.f.__gcs.write = NULL; f.f.__gcs.seek = NULL; f.f.__gcs.close = NULL;#endif f.f.__filedes = __STDIO_STREAM_FAKE_VSNPRINTF_FILEDES_NB; f.f.__modeflags = (__FLAG_NARROW|__FLAG_WRITEONLY|__FLAG_WRITING);#ifdef __UCLIBC_HAS_WCHAR__ f.f.__ungot_width[0] = 0;#endif /* __UCLIBC_HAS_WCHAR__ */#ifdef __STDIO_MBSTATE __INIT_MBSTATE(&(f.f.__state));#endif /* __STDIO_MBSTATE */#ifdef __UCLIBC_HAS_THREADS__ f.f.__user_locking = 1; /* Set user locking. */ __stdio_init_mutex(&f.f.__lock);#endif f.f.__nextopen = NULL; rv = vfprintf((FILE *) &f, format, arg); if (size) { if (f.bufpos == f.bufend) { --f.bufpos; } *f.bufpos = 0; } return rv;}#elif defined(__UCLIBC_HAS_GLIBC_CUSTOM_STREAMS__)typedef struct { size_t pos; size_t len; unsigned char *buf; FILE *fp;} __snpf_cookie;#define COOKIE ((__snpf_cookie *) cookie)static ssize_t snpf_write(register void *cookie, const char *buf, size_t bufsize){ size_t count; register char *p; /* Note: bufsize < SSIZE_MAX because of _stdio_WRITE. */ if (COOKIE->len > COOKIE->pos) { count = COOKIE->len - COOKIE->pos - 1; /* Leave space for nul. */ if (count > bufsize) { count = bufsize; } p = COOKIE->buf + COOKIE->pos; while (count) { *p++ = *buf++; --count; } *p = 0; } COOKIE->pos += bufsize; return bufsize;}#undef COOKIEint vsnprintf(char *__restrict buf, size_t size, const char * __restrict format, va_list arg){ FILE f; __snpf_cookie cookie; int rv; cookie.buf = buf; cookie.len = size; cookie.pos = 0; cookie.fp = &f; f.__cookie = &cookie; f.__gcs.write = snpf_write; f.__gcs.read = NULL; f.__gcs.seek = NULL; f.__gcs.close = NULL; f.__filedes = -1; /* For debugging. */ f.__modeflags = (__FLAG_NARROW|__FLAG_WRITEONLY|__FLAG_WRITING);#ifdef __UCLIBC_HAS_WCHAR__ f.__ungot_width[0] = 0;#endif /* __UCLIBC_HAS_WCHAR__ */#ifdef __STDIO_MBSTATE __INIT_MBSTATE(&(f.__state));#endif /* __STDIO_MBSTATE */#ifdef __UCLIBC_HAS_THREADS__ f.__user_locking = 1; /* Set user locking. */ __stdio_init_mutex(&f.__lock);#endif f.__nextopen = NULL; rv = vfprintf(&f, format, arg); return rv;}#else#warning Skipping vsnprintf since no buffering, no custom streams, and not old vfprintf!#ifdef __STDIO_HAS_VSNPRINTF#error WHOA! __STDIO_HAS_VSNPRINTF is defined!#endif#endif
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