Some uses of the 'string-buffer' module don't need the *printf implementation.
In order to eliminate it from linking, when linking statically, this patch
splits up the module into two compilation units.
(The alternative would be a separate module 'string-buffer-printf', but that
leads to an excessive number of modules, IMO.)
2024-09-24 Bruno Haible <br...@clisp.org>
string-buffer: Link to vasnprintf implementation only when needed.
* lib/string-buffer-printf.c: New file, extracted from
lib/string-buffer.c.
* lib/string-buffer.c: Don't include <stdarg.h>.
(sb_ensure_more_bytes): Declare. Make non-static.
(sb_appendvf, sb_appendf): Moved to lib/string-buffer-printf.c.
* modules/string-buffer (Files): Add lib/string-buffer-printf.c.
(Makefile.am): Arrange to compile string-buffer-printf.c.
diff --git a/lib/string-buffer-printf.c b/lib/string-buffer-printf.c
new file mode 100644
index 0000000000..16ef4e4144
--- /dev/null
+++ b/lib/string-buffer-printf.c
@@ -0,0 +1,189 @@
+/* A buffer that accumulates a string by piecewise concatenation.
+ Copyright (C) 2021-2024 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation, either version 3 of the
+ License, or (at your option) any later version.
+
+ This file is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <br...@clisp.org>, 2021. */
+
+#include <config.h>
+
+/* Specification. */
+#include "string-buffer.h"
+
+/* Undocumented. */
+extern int sb_ensure_more_bytes (struct string_buffer *buffer,
+ size_t increment);
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int
+sb_appendvf (struct string_buffer *buffer, const char *formatstring,
+ va_list list)
+{
+ va_list list_copy;
+
+ /* Make a bit of room, so that the probability that the first vsnprintf()
call
+ succeeds is high. */
+ size_t room = buffer->allocated - buffer->length;
+ if (room < 64)
+ {
+ if (sb_ensure_more_bytes (buffer, 64) < 0)
+ {
+ buffer->error = true;
+ return -1;
+ }
+ room = buffer->allocated - buffer->length;
+ }
+
+ va_copy (list_copy, list);
+
+ /* First vsnprintf() call. */
+ int ret = vsnprintf (buffer->data + buffer->length, room, formatstring,
list);
+ if (ret < 0)
+ {
+ /* Failed. */
+ buffer->error = true;
+ ret = -1;
+ }
+ else
+ {
+ if ((size_t) ret <= room)
+ {
+ /* The result has fit into room bytes. */
+ buffer->length += (size_t) ret;
+ ret = 0;
+ }
+ else
+ {
+ /* The result was truncated. Make more room, for a second
vsnprintf()
+ call. */
+ if (sb_ensure_more_bytes (buffer, (size_t) ret) < 0)
+ {
+ buffer->error = true;
+ ret = -1;
+ }
+ else
+ {
+ /* Second vsnprintf() call. */
+ room = buffer->allocated - buffer->length;
+ ret = vsnprintf (buffer->data + buffer->length, room,
+ formatstring, list_copy);
+ if (ret < 0)
+ {
+ /* Failed. */
+ buffer->error = true;
+ ret = -1;
+ }
+ else
+ {
+ if ((size_t) ret <= room)
+ {
+ /* The result has fit into room bytes. */
+ buffer->length += (size_t) ret;
+ ret = 0;
+ }
+ else
+ /* The return values of the vsnprintf() calls are not
+ consistent. */
+ abort ();
+ }
+ }
+ }
+ }
+
+ va_end (list_copy);
+ return ret;
+}
+
+int
+sb_appendf (struct string_buffer *buffer, const char *formatstring, ...)
+{
+ va_list args;
+
+ /* Make a bit of room, so that the probability that the first vsnprintf()
call
+ succeeds is high. */
+ size_t room = buffer->allocated - buffer->length;
+ if (room < 64)
+ {
+ if (sb_ensure_more_bytes (buffer, 64) < 0)
+ {
+ buffer->error = true;
+ return -1;
+ }
+ room = buffer->allocated - buffer->length;
+ }
+
+ va_start (args, formatstring);
+
+ /* First vsnprintf() call. */
+ int ret = vsnprintf (buffer->data + buffer->length, room, formatstring,
args);
+ if (ret < 0)
+ {
+ /* Failed. */
+ buffer->error = true;
+ ret = -1;
+ }
+ else
+ {
+ if ((size_t) ret <= room)
+ {
+ /* The result has fit into room bytes. */
+ buffer->length += (size_t) ret;
+ ret = 0;
+ }
+ else
+ {
+ /* The result was truncated. Make more room, for a second
vsnprintf()
+ call. */
+ if (sb_ensure_more_bytes (buffer, (size_t) ret) < 0)
+ {
+ buffer->error = true;
+ ret = -1;
+ }
+ else
+ {
+ /* Second vsnprintf() call. */
+ room = buffer->allocated - buffer->length;
+ va_end (args);
+ va_start (args, formatstring);
+ ret = vsnprintf (buffer->data + buffer->length, room,
+ formatstring, args);
+ if (ret < 0)
+ {
+ /* Failed. */
+ buffer->error = true;
+ ret = -1;
+ }
+ else
+ {
+ if ((size_t) ret <= room)
+ {
+ /* The result has fit into room bytes. */
+ buffer->length += (size_t) ret;
+ ret = 0;
+ }
+ else
+ /* The return values of the vsnprintf() calls are not
+ consistent. */
+ abort ();
+ }
+ }
+ }
+ }
+
+ va_end (args);
+ return ret;
+}
diff --git a/lib/string-buffer.c b/lib/string-buffer.c
index 6ea589d67d..221cd9191e 100644
--- a/lib/string-buffer.c
+++ b/lib/string-buffer.c
@@ -21,7 +21,10 @@
/* Specification. */
#include "string-buffer.h"
-#include <stdarg.h>
+/* Undocumented. */
+extern int sb_ensure_more_bytes (struct string_buffer *buffer,
+ size_t increment);
+
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -38,7 +41,7 @@ sb_init (struct string_buffer *buffer)
/* Ensures that INCREMENT bytes are available beyond the current used length
of BUFFER.
Returns 0, or -1 in case of out-of-memory error. */
-static int
+int
sb_ensure_more_bytes (struct string_buffer *buffer, size_t increment)
{
size_t incremented_length = buffer->length + increment;
@@ -91,165 +94,6 @@ sb_append (struct string_buffer *buffer, const char *str)
return 0;
}
-int
-sb_appendvf (struct string_buffer *buffer, const char *formatstring,
- va_list list)
-{
- va_list list_copy;
-
- /* Make a bit of room, so that the probability that the first vsnprintf()
call
- succeeds is high. */
- size_t room = buffer->allocated - buffer->length;
- if (room < 64)
- {
- if (sb_ensure_more_bytes (buffer, 64) < 0)
- {
- buffer->error = true;
- return -1;
- }
- room = buffer->allocated - buffer->length;
- }
-
- va_copy (list_copy, list);
-
- /* First vsnprintf() call. */
- int ret = vsnprintf (buffer->data + buffer->length, room, formatstring,
list);
- if (ret < 0)
- {
- /* Failed. */
- buffer->error = true;
- ret = -1;
- }
- else
- {
- if ((size_t) ret <= room)
- {
- /* The result has fit into room bytes. */
- buffer->length += (size_t) ret;
- ret = 0;
- }
- else
- {
- /* The result was truncated. Make more room, for a second
vsnprintf()
- call. */
- if (sb_ensure_more_bytes (buffer, (size_t) ret) < 0)
- {
- buffer->error = true;
- ret = -1;
- }
- else
- {
- /* Second vsnprintf() call. */
- room = buffer->allocated - buffer->length;
- ret = vsnprintf (buffer->data + buffer->length, room,
- formatstring, list_copy);
- if (ret < 0)
- {
- /* Failed. */
- buffer->error = true;
- ret = -1;
- }
- else
- {
- if ((size_t) ret <= room)
- {
- /* The result has fit into room bytes. */
- buffer->length += (size_t) ret;
- ret = 0;
- }
- else
- /* The return values of the vsnprintf() calls are not
- consistent. */
- abort ();
- }
- }
- }
- }
-
- va_end (list_copy);
- return ret;
-}
-
-int
-sb_appendf (struct string_buffer *buffer, const char *formatstring, ...)
-{
- va_list args;
-
- /* Make a bit of room, so that the probability that the first vsnprintf()
call
- succeeds is high. */
- size_t room = buffer->allocated - buffer->length;
- if (room < 64)
- {
- if (sb_ensure_more_bytes (buffer, 64) < 0)
- {
- buffer->error = true;
- return -1;
- }
- room = buffer->allocated - buffer->length;
- }
-
- va_start (args, formatstring);
-
- /* First vsnprintf() call. */
- int ret = vsnprintf (buffer->data + buffer->length, room, formatstring,
args);
- if (ret < 0)
- {
- /* Failed. */
- buffer->error = true;
- ret = -1;
- }
- else
- {
- if ((size_t) ret <= room)
- {
- /* The result has fit into room bytes. */
- buffer->length += (size_t) ret;
- ret = 0;
- }
- else
- {
- /* The result was truncated. Make more room, for a second
vsnprintf()
- call. */
- if (sb_ensure_more_bytes (buffer, (size_t) ret) < 0)
- {
- buffer->error = true;
- ret = -1;
- }
- else
- {
- /* Second vsnprintf() call. */
- room = buffer->allocated - buffer->length;
- va_end (args);
- va_start (args, formatstring);
- ret = vsnprintf (buffer->data + buffer->length, room,
- formatstring, args);
- if (ret < 0)
- {
- /* Failed. */
- buffer->error = true;
- ret = -1;
- }
- else
- {
- if ((size_t) ret <= room)
- {
- /* The result has fit into room bytes. */
- buffer->length += (size_t) ret;
- ret = 0;
- }
- else
- /* The return values of the vsnprintf() calls are not
- consistent. */
- abort ();
- }
- }
- }
- }
-
- va_end (args);
- return ret;
-}
-
void
sb_free (struct string_buffer *buffer)
{
diff --git a/modules/string-buffer b/modules/string-buffer
index 54da1db988..76c07d94ac 100644
--- a/modules/string-buffer
+++ b/modules/string-buffer
@@ -4,6 +4,7 @@ A buffer that accumulates a string by piecewise concatenation.
Files:
lib/string-buffer.h
lib/string-buffer.c
+lib/string-buffer-printf.c
Depends-on:
stdbool
@@ -14,7 +15,7 @@ vsnprintf-posix
configure.ac:
Makefile.am:
-lib_SOURCES += string-buffer.c
+lib_SOURCES += string-buffer.c string-buffer-printf.c
Include:
"string-buffer.h"
