Index: common/include/printf_core.h =================================================================== --- common/include/printf_core.h (revision 97f6b71fdbc9535de15d3b4ae8be377be2040150) +++ common/include/printf_core.h (revision 163e34ce66d8952017bc5a812affc2f72443b230) @@ -36,15 +36,17 @@ #define _LIBC_PRINTF_CORE_H_ +#include +#include #include -#include #include /** Structure for specifying output methods for different printf clones. */ typedef struct { - /* String output function, returns number of printed characters or EOF */ - int (*str_write)(const char *, size_t, void *); - - /* Wide string output function, returns number of printed characters or EOF */ - int (*wstr_write)(const char32_t *, size_t, void *); + /* + * String output function, returns EOK on success. + * Only returns an error when an irrecoverable failure occurs and + * the string cannot be fully output. + */ + errno_t (*write)(const char *, size_t, void *); /* User data - output stream specification, state, locks, etc. */ Index: common/printf/printf_core.c =================================================================== --- common/printf/printf_core.c (revision 97f6b71fdbc9535de15d3b4ae8be377be2040150) +++ common/printf/printf_core.c (revision 163e34ce66d8952017bc5a812affc2f72443b230) @@ -201,15 +201,10 @@ size_t *written_bytes) { - int written = ps->str_write(buf, n, ps->data); - if (written < 0) - return EIO; + errno_t rc = ps->write(buf, n, ps->data); + if (rc != EOK) + return rc; + _saturating_add(written_bytes, n); return EOK; - - #if 0 - errno_t rc = ps->write(buf, &n, ps->data); - _saturating_add(written_bytes, n); - return rc; - #endif } @@ -1466,6 +1461,4 @@ rc = _format_number(number, width, precision, base, flags, ps, &counter); - if (rc != EOK) - continue; } Index: common/stdc/snprintf.c =================================================================== --- common/stdc/snprintf.c (revision 163e34ce66d8952017bc5a812affc2f72443b230) +++ common/stdc/snprintf.c (revision 163e34ce66d8952017bc5a812affc2f72443b230) @@ -0,0 +1,60 @@ +/* + * Copyright (c) 2006 Josef Cejka + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * - The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** @addtogroup libc + * @{ + */ +/** @file + */ + +#include +#include + +/** Print formatted to the given buffer with limited size. + * + * @param str Buffer + * @param size Buffer size + * @param fmt Format string + * + * \see For more details about format string see printf_core. + * + */ +int snprintf(char *str, size_t size, const char *fmt, ...) +{ + va_list args; + va_start(args, fmt); + + int ret = vsnprintf(str, size, fmt, args); + + va_end(args); + + return ret; +} + +/** @} + */ Index: common/stdc/vsnprintf.c =================================================================== --- common/stdc/vsnprintf.c (revision 163e34ce66d8952017bc5a812affc2f72443b230) +++ common/stdc/vsnprintf.c (revision 163e34ce66d8952017bc5a812affc2f72443b230) @@ -0,0 +1,84 @@ +/* + * Copyright (c) 2006 Josef Cejka + * Copyright (c) 2025 Jiří Zárevúcky + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * - The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** @addtogroup libc + * @{ + */ +/** @file + */ + +#include +#include +#include +#include +#include +#include + +typedef struct { + char *dst; /* Destination */ + size_t left; +} vsnprintf_data_t; + +static int vsnprintf_str_write(const char *str, size_t size, void *data) +{ + vsnprintf_data_t *d = data; + size_t left = min(size, d->left); + if (left > 0) { + memcpy(d->dst, str, left); + d->dst += left; + d->left -= left; + } + return EOK; +} + +int vsnprintf(char *str, size_t size, const char *fmt, va_list ap) +{ + vsnprintf_data_t data = { + .dst = str, + .left = size ? size - 1 : 0, + }; + + printf_spec_t ps = { + vsnprintf_str_write, + &data + }; + + int written = printf_core(fmt, &ps, ap); + if (written < 0) + return written; + + /* Write the terminating NUL character. */ + if (size > 0) + data.dst[0] = 0; + + return written; +} + +/** @} + */