tag-util.[ch]: New files for common tagging routines

These are meant to be shared between notmuch-tag and notmuch-restore.

The bulk of the routines implement a "tag operation list" abstract
data type act as a structured representation of a set of tag
operations (typically coming from a single tag command or line of
input).

1 files changed, 135 insertions, 0 deletions

diff --git a/tag-util.h b/tag-util.h
new file mode 100644
index 00000000..99b0fa0b
--- /dev/null
+++ b/tag-util.h
@@ -0,0 +1,135 @@
+#ifndef _TAG_UTIL_H
+#define _TAG_UTIL_H
+
+#include "notmuch-client.h"
+
+typedef struct _tag_operation_t tag_operation_t;
+typedef struct _tag_op_list_t tag_op_list_t;
+
+/* Use powers of 2 */
+typedef enum {
+    TAG_FLAG_NONE = 0,
+
+    /* Operations are synced to maildir, if possible.
+     */
+    TAG_FLAG_MAILDIR_SYNC = (1 << 0),
+
+    /* Remove all tags from message before applying list.
+     */
+    TAG_FLAG_REMOVE_ALL = (1 << 1),
+
+    /* Don't try to avoid database operations. Useful when we
+     * know that message passed needs these operations.
+     */
+    TAG_FLAG_PRE_OPTIMIZED = (1 << 2),
+
+    /* Accept strange tags that might be user error;
+     * intended for use by notmuch-restore.
+     */
+    TAG_FLAG_BE_GENEROUS = (1 << 3)
+
+} tag_op_flag_t;
+
+/* These should obey the convention that fatal errors are negative,
+ * skipped lines are positive.
+ */
+typedef enum {
+    TAG_PARSE_OUT_OF_MEMORY = -1,
+
+    /* Line parsed successfuly. */
+    TAG_PARSE_SUCCESS = 0,
+
+    /* Line has a syntax error */
+    TAG_PARSE_INVALID = 1,
+
+    /* Line was blank or a comment */
+    TAG_PARSE_SKIPPED = 2
+
+} tag_parse_status_t;
+
+/* Parse a string of the following format:
+ *
+ * +<tag>|-<tag> [...] [--] <search-terms>
+ *
+ * Each line is interpreted similarly to "notmuch tag" command line
+ * arguments. The delimiter is one or more spaces ' '. Any characters
+ * in <tag> and <search-terms> MAY be hex encoded with %NN where NN is
+ * the hexadecimal value of the character. Any ' ' and '%' characters
+ * in <tag> and <search-terms> MUST be hex encoded (using %20 and %25,
+ * respectively). Any characters that are not part of <tag> or
+ * <search-terms> MUST NOT be hex encoded.
+ *
+ * Leading and trailing space ' ' is ignored. Empty lines and lines
+ * beginning with '#' are ignored.
+ *
+ *
+ * Output Parameters:
+ *	ops	contains a list of tag operations
+ *	query_str the search terms.
+ */
+tag_parse_status_t
+parse_tag_line (void *ctx, char *line,
+		tag_op_flag_t flags,
+		char **query_str, tag_op_list_t *ops);
+
+/*
+ * Create an empty list of tag operations
+ *
+ * ctx is passed to talloc
+ */
+
+tag_op_list_t *
+tag_op_list_create (void *ctx);
+
+/*
+ * Add a tag operation (delete iff remove == TRUE) to a list.
+ * The list is expanded as necessary.
+ */
+
+int
+tag_op_list_append (void *ctx,
+		    tag_op_list_t *list,
+		    const char *tag,
+		    notmuch_bool_t remove);
+
+/*
+ * Apply a list of tag operations, in order, to a given message.
+ *
+ * Flags can be bitwise ORed; see enum above for possibilies.
+ */
+
+notmuch_status_t
+tag_op_list_apply (notmuch_message_t *message,
+		   tag_op_list_t *tag_ops,
+		   tag_op_flag_t flags);
+
+/*
+ * Return the number of operations in a list
+ */
+
+size_t
+tag_op_list_size (const tag_op_list_t *list);
+
+/*
+ * Reset a list to contain no operations
+ */
+
+void
+tag_op_list_reset (tag_op_list_t *list);
+
+
+/*
+ *   return the i'th tag in the list
+ */
+
+const char *
+tag_op_list_tag (const tag_op_list_t *list, size_t i);
+
+/*
+ *   Is the i'th tag operation a remove?
+ */
+
+notmuch_bool_t
+tag_op_list_isremove (const tag_op_list_t *list, size_t i);
+
+#endif