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Diffstat (limited to 'src/basic/strxcpyx.c')
-rw-r--r-- | src/basic/strxcpyx.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/src/basic/strxcpyx.c b/src/basic/strxcpyx.c new file mode 100644 index 0000000..52b9565 --- /dev/null +++ b/src/basic/strxcpyx.c @@ -0,0 +1,145 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +/* + * Concatenates/copies strings. In any case, terminates in all cases + * with '\0' and moves the @dest pointer forward to the added '\0'. + * Returns the remaining size, and 0 if the string was truncated. + * + * Due to the intended usage, these helpers silently noop invocations + * having zero size. This is technically an exception to the above + * statement "terminates in all cases". It's unexpected for such calls to + * occur outside of a loop where this is the preferred behavior. + */ + +#include <stdarg.h> +#include <stdio.h> +#include <string.h> + +#include "string-util.h" +#include "strxcpyx.h" + +size_t strnpcpy_full(char **dest, size_t size, const char *src, size_t len, bool *ret_truncated) { + bool truncated = false; + + assert(dest); + assert(src); + + if (size == 0) { + if (ret_truncated) + *ret_truncated = len > 0; + return 0; + } + + if (len >= size) { + if (size > 1) + *dest = mempcpy(*dest, src, size-1); + size = 0; + truncated = true; + } else if (len > 0) { + *dest = mempcpy(*dest, src, len); + size -= len; + } + + if (ret_truncated) + *ret_truncated = truncated; + + *dest[0] = '\0'; + return size; +} + +size_t strpcpy_full(char **dest, size_t size, const char *src, bool *ret_truncated) { + assert(dest); + assert(src); + + return strnpcpy_full(dest, size, src, strlen(src), ret_truncated); +} + +size_t strpcpyf_full(char **dest, size_t size, bool *ret_truncated, const char *src, ...) { + bool truncated = false; + va_list va; + int i; + + assert(dest); + assert(src); + + va_start(va, src); + i = vsnprintf(*dest, size, src, va); + va_end(va); + + if (i < (int) size) { + *dest += i; + size -= i; + } else { + size = 0; + truncated = i > 0; + } + + if (ret_truncated) + *ret_truncated = truncated; + + return size; +} + +size_t strpcpyl_full(char **dest, size_t size, bool *ret_truncated, const char *src, ...) { + bool truncated = false; + va_list va; + + assert(dest); + assert(src); + + va_start(va, src); + do { + bool t; + + size = strpcpy_full(dest, size, src, &t); + truncated = truncated || t; + src = va_arg(va, char *); + } while (src); + va_end(va); + + if (ret_truncated) + *ret_truncated = truncated; + return size; +} + +size_t strnscpy_full(char *dest, size_t size, const char *src, size_t len, bool *ret_truncated) { + char *s; + + assert(dest); + assert(src); + + s = dest; + return strnpcpy_full(&s, size, src, len, ret_truncated); +} + +size_t strscpy_full(char *dest, size_t size, const char *src, bool *ret_truncated) { + assert(dest); + assert(src); + + return strnscpy_full(dest, size, src, strlen(src), ret_truncated); +} + +size_t strscpyl_full(char *dest, size_t size, bool *ret_truncated, const char *src, ...) { + bool truncated = false; + va_list va; + char *s; + + assert(dest); + assert(src); + + va_start(va, src); + s = dest; + do { + bool t; + + size = strpcpy_full(&s, size, src, &t); + truncated = truncated || t; + src = va_arg(va, char *); + } while (src); + va_end(va); + + if (ret_truncated) + *ret_truncated = truncated; + + return size; +} |