common: Consolidate Assuan server argument handling.

* common/Makefile.am (common_sources): Add new files.
* common/server-help.c: New file.
* common/server-help.h: Likewise.
* agent/command.c: Drop argument handling primitives in favor of using
the consolidated ones.
* dirmngr/server.c: Likewise.
* g10/server.c: Likewise.
* g13/server.c: Likewise.
* scd/command.c: Likewise.
* sm/server.c: Likewise.

Signed-off-by: Justus Winter <[email protected]>

1 files changed, 137 insertions, 0 deletions

diff --git a/common/server-help.c b/common/server-help.c
new file mode 100644
index 000000000..2a59dc63e
--- /dev/null
+++ b/common/server-help.c
@@ -0,0 +1,137 @@
+/* server-help.h - Helper functions for writing Assuan servers.
+ *	Copyright (C) 2003, 2009, 2010 g10 Code GmbH
+ *
+ * This file is part of GnuPG.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of either
+ *
+ *   - 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.
+ *
+ * or
+ *
+ *   - the GNU General Public License as published by the Free
+ *     Software Foundation; either version 2 of the License, or (at
+ *     your option) any later version.
+ *
+ * or both in parallel, as here.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <string.h>
+
+#include "server-help.h"
+#include "util.h"
+
+/* Skip over options in LINE.
+
+   Blanks after the options are also removed.  Options are indicated
+   by two leading dashes followed by a string consisting of non-space
+   characters.  The special option "--" indicates an explicit end of
+   options; all what follows will not be considered an option.  The
+   first no-option string also indicates the end of option parsing. */
+char *
+skip_options (const char *line)
+{
+  while (spacep (line))
+    line++;
+  while (*line == '-' && line[1] == '-')
+    {
+      while (*line && !spacep (line))
+        line++;
+      while (spacep (line))
+        line++;
+    }
+  return (char*) line;
+}
+
+
+/* Check whether the option NAME appears in LINE.  */
+int
+has_option (const char *line, const char *name)
+{
+  const char *s;
+  int n = strlen (name);
+
+  s = strstr (line, name);
+  if (s && s >= skip_options (line))
+    return 0;
+  return (s && (s == line || spacep (s-1)) && (!s[n] || spacep (s+n)));
+}
+
+
+/* Same as has_option but only considers options at the begin of the
+   line.  This is useful for commands which allow arbitrary strings on
+   the line.  */
+int
+has_leading_option (const char *line, const char *name)
+{
+  const char *s;
+  int n;
+
+  if (name[0] != '-' || name[1] != '-' || !name[2] || spacep (name+2))
+    return 0;
+  n = strlen (name);
+  while ( *line == '-' && line[1] == '-' )
+    {
+      s = line;
+      while (*line && !spacep (line))
+        line++;
+      if (n == (line - s) && !strncmp (s, name, n))
+        return 1;
+      while (spacep (line))
+        line++;
+    }
+  return 0;
+}
+
+
+/* Same as has_option but does only test for the name of the option
+   and ignores an argument, i.e. with NAME being "--hash" it would
+   return a pointer for "--hash" as well as for "--hash=foo".  If
+   there is no such option NULL is returned.  The pointer returned
+   points right behind the option name, this may be an equal sign, Nul
+   or a space.  */
+const char *
+has_option_name (const char *line, const char *name)
+{
+  const char *s;
+  int n = strlen (name);
+
+  s = strstr (line, name);
+  return (s && (s == line || spacep (s-1))
+          && (!s[n] || spacep (s+n) || s[n] == '=')) ? (s+n) : NULL;
+}
+
+
+/* Return a pointer to the argument of the option with NAME.  If such
+   an option is not given, NULL is returned. */
+char *
+option_value (const char *line, const char *name)
+{
+  char *s;
+  int n = strlen (name);
+
+  s = strstr (line, name);
+  if (s && s >= skip_options (line))
+    return NULL;
+  if (s && (s == line || spacep (s-1))
+      && s[n] && (spacep (s+n) || s[n] == '='))
+    {
+      s += n + 1;
+      s += strspn (s, " ");
+      if (*s && !spacep(s))
+        return s;
+    }
+  return NULL;
+}