diff --git a/libavutil/bprint.c b/libavutil/bprint.c index 115bf0c8de..646f0aab5d 100644 --- a/libavutil/bprint.c +++ b/libavutil/bprint.c @@ -78,6 +78,15 @@ void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max) av_bprint_alloc(buf, size_init - 1); } +void av_bprint_init_for_buffer(AVBPrint *buf, char *buffer, unsigned size) +{ + buf->str = buffer; + buf->len = 0; + buf->size = size; + buf->size_max = size; + *buf->str = 0; +} + void av_bprintf(AVBPrint *buf, const char *fmt, ...) { unsigned room; @@ -178,6 +187,7 @@ static void bprint_pascal(AVBPrint *b, unsigned size) int main(void) { AVBPrint b; + char buf[256]; av_bprint_init(&b, 0, -1); bprint_pascal(&b, 5); @@ -208,6 +218,10 @@ int main(void) bprint_pascal(&b, 25); printf("Long text count only buffer: %zu/%u\n", strlen(b.str), b.len); + av_bprint_init_for_buffer(&b, buf, sizeof(buf)); + bprint_pascal(&b, 25); + printf("Long text count only buffer: %zu/%u\n", strlen(buf), b.len); + return 0; } diff --git a/libavutil/bprint.h b/libavutil/bprint.h index ad65afec69..60e464e10b 100644 --- a/libavutil/bprint.h +++ b/libavutil/bprint.h @@ -99,6 +99,17 @@ void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max); #define AV_BPRINT_SIZE_AUTOMATIC 1 #define AV_BPRINT_SIZE_COUNT_ONLY 0 +/** + * Init a print buffer using a pre-existing buffer. + * + * The buffer will not be reallocated. + * + * @param buf buffer structure to init + * @param buffer byte buffer to use for the string data + * @param size size of buffer + */ +void av_bprint_init_for_buffer(AVBPrint *buf, char *buffer, unsigned size); + /** * Append a formated string to a print buffer. */