diff --git a/misc.c b/misc.c index 5ff403d6..7a7cc194 100644 --- a/misc.c +++ b/misc.c @@ -394,22 +394,16 @@ int toint(unsigned u) * directive we don't know about, we should panic and die rather * than run any risk. */ -char *dupprintf(const char *fmt, ...) +static char *dupvprintf_inner(char *buf, int oldlen, int oldsize, + const char *fmt, va_list ap) { - char *ret; - va_list ap; - va_start(ap, fmt); - ret = dupvprintf(fmt, ap); - va_end(ap); - return ret; -} -char *dupvprintf(const char *fmt, va_list ap) -{ - char *buf; int len, size; - buf = snewn(512, char); - size = 512; + size = oldsize - oldlen; + if (size == 0) { + size = 512; + buf = sresize(buf, oldlen + size, char); + } while (1) { #if defined _WINDOWS && _MSC_VER < 1900 /* 1900 == VS2015 has real snprintf */ @@ -420,7 +414,7 @@ char *dupvprintf(const char *fmt, va_list ap) * XXX some environments may have this as __va_copy() */ va_list aq; va_copy(aq, ap); - len = vsnprintf(buf, size, fmt, aq); + len = vsnprintf(buf + oldlen, size, fmt, aq); va_end(aq); #else /* Ugh. No va_copy macro, so do something nasty. @@ -431,7 +425,7 @@ char *dupvprintf(const char *fmt, va_list ap) * (indeed, it has been observed to). * XXX the autoconf manual suggests that using memcpy() will give * "maximum portability". */ - len = vsnprintf(buf, size, fmt, ap); + len = vsnprintf(buf + oldlen, size, fmt, ap); #endif if (len >= 0 && len < size) { /* This is the C99-specified criterion for snprintf to have @@ -446,10 +440,65 @@ char *dupvprintf(const char *fmt, va_list ap) * buffer wasn't big enough, so we enlarge it a bit and hope. */ size += 512; } - buf = sresize(buf, size, char); + buf = sresize(buf, oldlen + size, char); } } +char *dupvprintf(const char *fmt, va_list ap) +{ + return dupvprintf_inner(NULL, 0, 0, fmt, ap); +} +char *dupprintf(const char *fmt, ...) +{ + char *ret; + va_list ap; + va_start(ap, fmt); + ret = dupvprintf(fmt, ap); + va_end(ap); + return ret; +} + +struct strbuf { + char *s; + int len, size; +}; +strbuf *strbuf_new(void) +{ + strbuf *buf = snew(strbuf); + buf->len = 0; + buf->size = 512; + buf->s = snewn(buf->size, char); + *buf->s = '\0'; + return buf; +} +void strbuf_free(strbuf *buf) +{ + sfree(buf->s); + sfree(buf); +} +char *strbuf_str(strbuf *buf) +{ + return buf->s; +} +char *strbuf_to_str(strbuf *buf) +{ + char *ret = buf->s; + sfree(buf); + return ret; +} +void strbuf_catfv(strbuf *buf, const char *fmt, va_list ap) +{ + buf->s = dupvprintf_inner(buf->s, buf->len, buf->size, fmt, ap); + buf->len += strlen(buf->s + buf->len); +} +void strbuf_catf(strbuf *buf, const char *fmt, ...) +{ + va_list ap; + va_start(ap, fmt); + strbuf_catfv(buf, fmt, ap); + va_end(ap); +} + /* * Read an entire line of text from a file. Return a buffer * malloced to be as big as necessary (caller must free). diff --git a/misc.h b/misc.h index ce927ec5..9ab21a0b 100644 --- a/misc.h +++ b/misc.h @@ -38,6 +38,13 @@ char *dupprintf(const char *fmt, ...) ; char *dupvprintf(const char *fmt, va_list ap); void burnstr(char *string); +typedef struct strbuf strbuf; +strbuf *strbuf_new(void); +void strbuf_free(strbuf *buf); +char *strbuf_str(strbuf *buf); /* does not free buf */ +char *strbuf_to_str(strbuf *buf); /* does free buf, but you must free result */ +void strbuf_catf(strbuf *buf, const char *fmt, ...); +void strbuf_catfv(strbuf *buf, const char *fmt, va_list ap); /* String-to-Unicode converters that auto-allocate the destination and * work around the rather deficient interface of mb_to_wc.