4 files changed, 219 insertions, 38 deletions

diff --git a/lib/libc/stdio/Makefile.inc b/lib/libc/stdio/Makefile.inc
index 5ca501621a49..b9c02a41f40c 100644
--- a/lib/libc/stdio/Makefile.inc
+++ b/lib/libc/stdio/Makefile.inc
@@ -3,16 +3,16 @@
 # stdio sources
 .PATH: ${.CURDIR}/stdio
 
-SRCS+=	clrerr.c fclose.c fdopen.c feof.c ferror.c fflush.c fgetc.c \
-	fgetln.c fgetpos.c fgets.c fileno.c findfp.c flags.c fopen.c \
+SRCS+=	asprintf.c clrerr.c fclose.c fdopen.c feof.c ferror.c fflush.c \
+	fgetc.c fgetln.c fgetpos.c fgets.c fileno.c findfp.c flags.c fopen.c \
 	fprintf.c fpurge.c fputc.c fputs.c fread.c freopen.c fscanf.c \
 	fseek.c fsetpos.c ftell.c funopen.c fvwrite.c fwalk.c fwrite.c \
 	getc.c getchar.c gets.c getw.c makebuf.c mktemp.c perror.c \
 	printf.c putc.c putchar.c puts.c putw.c refill.c remove.c rewind.c \
 	rget.c scanf.c setbuf.c setbuffer.c setvbuf.c snprintf.c sprintf.c \
-	sscanf.c stdio.c tempnam.c tmpfile.c tmpnam.c ungetc.c vfprintf.c \
-	vfscanf.c vprintf.c vscanf.c vsnprintf.c vsprintf.c vsscanf.c \
-	wbuf.c wsetup.c
+	sscanf.c stdio.c tempnam.c tmpfile.c tmpnam.c ungetc.c vasprintf.c \
+	vfprintf.c vfscanf.c vprintf.c vscanf.c vsnprintf.c vsprintf.c \
+	vsscanf.c wbuf.c wsetup.c
 
 MAN3+=	stdio/fclose.3 stdio/ferror.3 stdio/fflush.3 stdio/fgetln.3 \
 	stdio/fgets.3 stdio/fopen.3 stdio/fputs.3 stdio/fread.3 stdio/fseek.3 \
diff --git a/lib/libc/stdio/asprintf.c b/lib/libc/stdio/asprintf.c
new file mode 100644
index 000000000000..9b4d05b4397b
--- /dev/null
+++ b/lib/libc/stdio/asprintf.c
@@ -0,0 +1,59 @@
+/*-
+ * Copyright (c) 1996  Peter Wemm <peter@freebsd.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
+ */
+
+#if defined(LIBC_RCS) && !defined(lint)
+static char rcsid[] = "$Id$";
+#endif /* LIBC_RCS and not lint */
+
+#include <stdio.h>
+#if __STDC__
+#include <stdarg.h>
+#else
+#include <varargs.h>
+#endif
+
+#if __STDC__
+int
+asprintf(char **str, char const *fmt, ...)
+#else
+int
+asprintf(str, fmt, va_alist)
+	char **str;
+	char *fmt;
+	va_dcl
+#endif
+{
+	int ret;
+	va_list ap;
+
+#if __STDC__
+	va_start(ap, fmt);
+#else
+	va_start(ap);
+#endif
+	ret = vasprintf(str, fmt, ap);
+	va_end(ap);
+	return (ret);
+}
diff --git a/lib/libc/stdio/printf.3 b/lib/libc/stdio/printf.3
index 4238a90a889e..e675b3eda99b 100644
--- a/lib/libc/stdio/printf.3
+++ b/lib/libc/stdio/printf.3
@@ -43,10 +43,12 @@
 .Nm fprintf ,
 .Nm sprintf ,
 .Nm snprintf ,
+.Nm asprintf ,
 .Nm vprintf ,
 .Nm vfprintf,
 .Nm vsprintf ,
-.Nm vsnprintf
+.Nm vsnprintf ,
+.Nm vasprintf
 .Nd formatted output conversion
 .Sh SYNOPSIS
 .Fd #include <stdio.h>
@@ -58,8 +60,8 @@
 .Fn sprintf "char *str" "const char *format" ...
 .Ft int
 .Fn snprintf "char *str" "size_t size" "const char *format" ...
-.\" .Ft int
-.\" .Fn smprintf "const char *format" ...
+.Ft int
+.Fn asprintf "char **ret" "const char *format" ...
 .Fd #include <stdarg.h>
 .Ft int
 .Fn vprintf "const char *format" "va_list ap"
@@ -69,8 +71,8 @@
 .Fn vsprintf "char *str" "char *format" "va_list ap"
 .Ft int
 .Fn vsnprintf "char *str" "size_t size" "const char *format" "va_list ap"
-.\" .Ft int
-.\" .Fn vsmprintf "const char *format" "va_list ap"
+.Ft int
+.Fn vasprintf "char **ret" "const char *format" "va_list ap"
 .Sh DESCRIPTION
 The
 .Fn printf
@@ -94,45 +96,47 @@ write output to the given output
 and
 .Fn vsnprintf
 write to the character string
-.Fa str .
-.\" .IR str ;
-.\" and
-.\" .I smprintf
-.\" and
-.\" .I vsmprintf
-.\" dynamically allocate a new string with
-.\" .IR malloc .
+.Fa str ;
+and
+.Fn asprintf
+and
+.Fn vasprintf
+dynamically allocate a new string with
+.Xr malloc 3
+/
+.Xr realloc 3 .
+.Pp
 These functions write the output under the control of a
 .Fa format
 string that specifies how subsequent arguments
 (or arguments accessed via the variable-length argument facilities of
 .Xr stdarg 3 )
 are converted for output.
-.\" Except for
-.\" .I smprintf
-.\" and
-.\" .IR vsmprintf ,
-.\" all of these functions return
+.Pp
 These functions return
 the number of characters printed
 (not including the trailing
 .Ql \e0
 used to end output to strings).
-.\" .I Smprintf
-.\" and
-.\" .I vsmprintf
-.\" return a pointer to a string of an appropriate length;
-.\" this pointer should be passed to
-.\" .I free
-.\" to release the associated storage
-.\" when it is no longer needed.
-.\" If sufficient space is not avaliable,
-.\" .I smprintf
-.\" and
-.\" .I vsmprintf
-.\" will return
-.\" .SM
-.\" .BR
+.Pp
+.Fn Asprintf
+and
+.Fn vasprintf
+return a pointer to a buffer sufficiently large to hold the
+string in the
+.Fa ret
+argument;
+This pointer should be passed to
+.Xr free 3
+to release the allocated storage when it is no longer needed.
+If sufficient space cannot be allocated, 
+.Fn asprintf
+and
+.Fn vasprintf
+will return -1 and set
+.Fa ret
+to be a NULL pointer.
+.Pp
 .Fn Snprintf
 and
 .Fn vsnprintf
@@ -147,6 +151,7 @@ if the return value is greater than or equal to the
 .Fa size
 argument, the string was too short
 and some of the printed characters were discarded.
+.Pp
 .Fn Sprintf
 and
 .Fn vsprintf
@@ -600,6 +605,15 @@ The functions
 and
 .Fn vsnprintf
 are new to this release.
+.Pp
+The functions
+.Fn asprintf
+and
+.Fn vasprintf
+first appeared in the GNU C library.  This implementation is thought
+to be compatable but is not derived from the GNU code.  This implementation
+was written by Peter Wemm <peter@FreeBSD.org> and first appeared in
+FreeBSD-2.2.
 .Sh BUGS
 The conversion formats
 .Cm \&%D ,
diff --git a/lib/libc/stdio/vasprintf.c b/lib/libc/stdio/vasprintf.c
new file mode 100644
index 000000000000..bec579a7a9de
--- /dev/null
+++ b/lib/libc/stdio/vasprintf.c
@@ -0,0 +1,108 @@
+/*-
+ * Copyright (c) 1996  Peter Wemm <peter@freebsd.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
+ */
+
+#if defined(LIBC_RCS) && !defined(lint)
+static char rcsid[] = "$Id$";
+#endif /* LIBC_RCS and not lint */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if __STDC__
+#include <stdarg.h>
+#else
+#include <varargs.h>
+#endif
+
+#define CHUNK_SPARE 128 /* how much spare to allocate to avoid realloc calls */
+
+struct bufcookie {
+	char	*base;	/* start of buffer */
+	int	size;
+	int	left;
+};
+
+static int
+writehook(cookie, buf, len)
+	void *cookie;
+	char *buf;
+	int   len;
+{
+	struct bufcookie *h = (struct bufcookie *)cookie;
+
+	if (len == 0)
+		return 0;
+
+	if (len > h->left) {
+		/* grow malloc region */
+		h->left = h->left + len + CHUNK_SPARE;
+		h->size = h->size + len + CHUNK_SPARE;
+		h->base = realloc(h->base, h->size);
+		if (h->base == NULL)
+			return (-1);
+	}
+	/* "write" it */
+	(void)memcpy(h->base + h->size - h->left, buf, len);
+	h->left -= len;
+	return (0);
+}
+
+
+int
+vasprintf(str, fmt, ap)
+	char **str;
+	const char *fmt;
+	va_list ap;
+{
+	int ret;
+	FILE *f;
+	struct bufcookie h;
+
+	h.base = malloc(CHUNK_SPARE);
+	if (h.base == NULL)
+		return (-1);
+	h.size = CHUNK_SPARE;
+	h.left = CHUNK_SPARE;
+
+	f = funopen(&h, NULL, writehook, NULL, NULL);
+	if (f == NULL) {
+		free(h.base);
+		return (-1);
+	}
+	ret = vfprintf(f, fmt, ap);
+	fclose(f);
+	if (ret < 0) {
+		free(h.base);
+		return (-1);
+	}
+	if (h.base == NULL)	/* failed to realloc in writehook */
+		return (-1);
+
+	h.base[h.size - h.left] = '\0';
+	*str = realloc(h.base, h.size - h.left + 1);
+	if (*str == NULL)	/* failed to realloc it to actual size */
+		return -1;
+	return (ret);
+}