[PATCH] Add strndup implementation for systems with lack of it

[Vladimir Marek]

From: Vladimir Marek

Solaris 10 FCS (first release) does not have strndup implementation.

Signed-off-by: Vladimir Marek 
---
 configure.ac |    2 +-
 strndup.c    |   23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 strndup.c

diff --git a/configure.ac b/configure.ac
index a92e81c..5d20cd9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -371,7 +371,7 @@ AC_CHECK_TYPE(ssize_t, int)

AC_CHECK_FUNCS(fgetpos memmove setegid srand48 strerror)

-AC_REPLACE_FUNCS([setenv strcasecmp strdup strsep strtok_r wcscasecmp])
+AC_REPLACE_FUNCS([setenv strcasecmp strdup strsep strtok_r wcscasecmp strndup])
 AC_REPLACE_FUNCS([strcasestr mkdtemp])

AC_CHECK_FUNC(getopt)
diff --git a/strndup.c b/strndup.c
new file mode 100644
index 0000000..81557ba
--- /dev/null
+++ b/strndup.c
@@ -0,0 +1,23 @@
+/* Solaris 10 FCS does not have strndup */
+
+#include <string.h>
+#include <stdlib.h>
+
+char *
+strndup(const char *s, size_t n)
+{
+    size_t len;
+    char *ret;
+                                                                                                                                                             
+    if (!s)
+        return (char *)NULL;
+                                                                                                                                                             
+    len = strlen(s);
+    if (n < len)
+        len = n;
+
+    ret = malloc(len + 1); /* To store '\0' */
+    memcpy(ret, s, len);
+    ret[len] = '\0';
+    return ret;
+}

[Karel Zak]

On Tue, Apr 16, 2013 at 03:22:18PM +0200, [e-mail] wrote:
> +char *
> +strndup(const char *s, size_t n)
> +{
> size_t len;
> char *ret;
> if (!s)
>    return (char *)NULL;
> len = strlen(s);

It would be better to use strnlen() otherwise you cannot use
 the strndup() for unterminated strings.
> if (n < len)
>    len = n;
> ret = malloc(len + 1); /* To store '\0' */

if (!ret)
    return NULL;
> memcpy(ret, s, len);
> ret[len] = '\0';
> return ret;
>
> +}

I have applied a little bit different implementation. Please, git pull
 and test it. Thanks for your report!

Karel

[Vladimir Marek]

> I have applied a little bit different implementation. Please, git pull
>  and test it. Thanks for your report!

Oh yes, your implementation is clearly better and I can confirm it
works.

In the meantime mutt started to use mkdtemp ... But that's up to
'official' mutt to handle.

Thank you