[PATCH 25 of 55 RFC c-hglib:level1] hg_heads: creating a high level function for mercurial heads command

[Iulian Stana]

# HG changeset patch
# User Iulian Stana <julian.stana at gmail.com>
# Date 1379112129 -10800
#      Sat Sep 14 01:42:09 2013 +0300
# Node ID 5a4400516c39d59eaedd9649728027a05f3bc1a9
# Parent  72ea63f42ec0e0f871d8c6cd9edb3c093e2df439
hg_heads: creating a high level function for mercurial heads command

diff --git a/client.c b/client.c
--- a/client.c
+++ b/client.c
@@ -814,6 +814,27 @@
 	return gbuf;
 }
 
+/* The high level heads command for hglib API. */
+hg_csetstream_buffer *hg_heads(hg_handle *handle, int (*callback)
+			(const char *msg, size_t len), char *argument[])
+{
+	hg_csetstream_buffer *cbuf = malloc(sizeof(hg_csetstream_buffer));
+	cbuf->handle = handle;
+
+	cbuf->command = cmdbuilder("heads", argument, "--template", CHANGESET,
+							NULL);
+
+	if(hg_rawcommand(handle, cbuf->command) < 0){
+		return NULL;
+	}
+
+	cbuf->callback = callback;
+	cbuf->buffer = NULL;
+	cbuf->buf_size = 0;
+
+	return cbuf;
+}
+
 /* The yield next step. Getting the next entry. */
 int hg_fetch_entry(hg_stream_buffer *stream, int (*detect_byte)(char *buff, 
 			int buf_size, int data_on_pipe), int func_type)
diff --git a/client.h b/client.h
--- a/client.h
+++ b/client.h
@@ -1067,6 +1067,54 @@
 			(const char *msg, size_t len), char *argument[]);
 
 /**
+ * \brief hg_heads command for hglib API.
+ *
+ * With no arguments, show all open branch heads in the repository. Branch heads
+ * are changesets that have no descendants on the same branch. They are where
+ * development generally takes place and are the usual targets for update and
+ * merge operations.
+ *
+ * If one or more REVs are given, only open branch heads on the branches
+ * associated with the specified changesets are shown. This means that you can
+ * use hg heads . to see the heads on the currently checked-out branch.
+ *
+ * If -c/--closed is specified, also show branch heads marked closed (see hg
+ * commit --close-branch).
+ *
+ * If STARTREV is specified, only those heads that are descendants of STARTREV
+ * will be displayed.
+ *
+ * If -t/--topo is specified, named branch mechanics will be ignored and only
+ * topological heads (changesets with no children) will be shown.
+ *
+ * Options/Argument list option:
+ *
+ *	-r, --rev		show only heads which are descendants of 
+ *				STARTREV
+ *	-t, --topo		show topological heads only
+ *	-a, --active	show active branchheads only (DEPRECATED)
+ *	-c, --closed	show normal and closed branch heads
+ *	--style		display using template map file
+ *	--template		display with template
+ *
+ * To get heads information use the returned hg_csetstream_buffer structure with
+ * hg_fetch_cset_entry() function.
+ *
+ * \param handle The handle of the connection, wherewith I want to communicate
+ * \param callback A function that will handle error data. 
+ *                 A NULL pointer will ignore error data.
+ * \param argument The option list. Will contain all option that you wish.
+ * \retval hg_csetstream_buffer A pointer to hg_csetstream_buffer structure if 
+ *                              successful
+ * \retval NULL to indicate an error, with errno set appropriately.
+ *
+ * errno can be:
+ *      - hg_rawcommand errors
+ * */
+hg_csetstream_buffer *hg_heads(hg_handle *handle, int (*callback)
+			(const char *msg, size_t len), char *argument[]);
+			
+/**
  * \brief The yield mechanism that will get the next entry.
  *
  * This function is used inside of hg_fetch_cset_entry() and hg_fetch_line_entry()