Patchwork [3,of,3,V4,RFC] model (2): c-hglib: hg_add() level 1 function

diff --git a/client.c b/client.c
--- a/client.c
+++ b/client.c
@@ -17,7 +17,57 @@ 
 #define CHANGESET "\\0{rev}\\n{node}\\n{tags}\\n{branch}\\n{author}\
 						\\n{date|isodate}\\n{desc}"
 
+/* return the output data. */
+char *get_output_data(hg_handle *handle)
+{
+       return handle->out_data;
+}
 
+/* Read and add to some pointers the received data from cmdserver. */
+int runcommand(hg_handle *handle, int (*callback)(const char *msg, size_t len),
+				char *(*prompt)(const char *msg, size_t len))
+{
+	char buff[4096];
+	int exitcode;
+	int ns;
+	char *err = "unexpected data on required channel";
+	char *w_data;
+	while(hg_next_channel(handle) != 'r'){
+		/* output channels 'o', 'e' channels verify in rawread func. */
+		while(ns = hg_rawread(handle, buff, 4096), ns > 0){
+			if(hg_current_channel(handle) == 'o'){
+				char *out = handle->out_data;
+				adding_data(&handle->out_data, buff,
+					(!out)? 0 : handle->out_data_size, ns);
+				handle->out_data_size += ns;
+			}
+			else if(hg_current_channel(handle) == 'e'){
+				if(callback)
+					callback(buff, strlen(buff));
+			}
+		}
+		switch (hg_next_channel(handle)){
+			case 'I':
+				break;
+			case 'L':
+				w_data = prompt(handle->out_data, 
+						strlen(handle->out_data));
+				hg_rawwrite(handle, w_data, strlen(w_data));
+				break;
+			case 'r':
+				break;
+		/* a channel that we don't know and can't ignore*/
+			default:
+				if(callback)
+					callback(err, strlen(err));
+				return 1;
+		}
+	}
+	if(hg_next_channel(handle) == 'r'){
+		exitcode = hg_exitcode(handle);
+	}
+	return exitcode;
+}
 
 /**
  * \brief 'Parse a changeset'. It's more like pointing to the correct position.
@@ -91,6 +141,22 @@ 
 	return new_cset_size;
 }
 
+/* The high level add command for hglib API.*/
+int hg_add(hg_handle *handle, int (*callback)(const char *msg, size_t len), 
+							char *argument[])
+{
+	int exitcode;
+	char **command = cmdbuilder("add", argument, NULL);
+
+	if(hg_rawcommand(handle, command) < 0){
+		return -1;
+	}
+	free(command);
+
+	exitcode = runcommand(handle, callback, NULL);
+
+	return exitcode;
+}
 
 /* The high level log command for hglib API. */
 hg_csetstream_buffer *hg_log(hg_handle *handle, char *option[])
diff --git a/client.h b/client.h
--- a/client.h
+++ b/client.h
@@ -233,6 +233,30 @@ 
  * */
 int hg_exitcode(hg_handle *handle);
 
+/* return the output data. */
+char *get_output_data(hg_handle *handle);
+
+/**
+ * \brief hg_add command for hglib API.
+ *
+ * Add the specified files on the next commit.
+ * If no files are given, add all files to the repository.
+ *
+ *      dryrun - do no perform actions
+ *      subrepos - recurse into subrepositories
+ *      include - include names matching the given patterns
+ *      exclude - exclude names matching the given patterns
+ *
+ * \param handle The handle of the connection, wherewith I want to communicate
+ * \param option The option list for mercurial add command.
+ * \retval exitcode  To indicate the end of add_command.
+ *
+ * errno can be:
+ *      - hg_rawcommand errors
+ * */
+int hg_add(hg_handle *handle, int (*callback)(const char *msg, size_t len), 
+							char *argument[]);
+
 /**
  * \brief hg_log command for hglib API.
  *
diff --git a/main.c b/main.c
--- a/main.c
+++ b/main.c
@@ -89,11 +89,16 @@ 
 {
 	printf("Select test case to run:\n");
 	printf("1) log \n");
+	printf("2) add \n");
 	printf("\n");
 	printf("Your choice: ");
 }
 
-
+int callback(const char *msg, size_t len)
+{
+	printf("message = %s\n", msg);
+	return 1;
+}
 
 /***** Main function. *******/
 /**
@@ -106,7 +111,7 @@ 
 
 	print_select_case();
 	scanf("%d", &select_case);
-	if(select_case < 1 || select_case > 1){
+	if(select_case < 1 || select_case > 2){
 		printf("Your choice is not an option...\n");
 		return -1;
 	}
@@ -122,6 +127,19 @@ 
 			hg_close(&handle);
 			clean_tmp();
 			break;
+		case 2:
+			setup_tmp();
+			
+			system("touch 'foo_bar'");
+
+			handle = hg_open(NULL, "");
+			hg_add(handle, &callback, NULL);
+			char *commit_arg[] = {"-m", "-l", NULL};
+			system("hg st");
+			hg_commit(handle, &callback, commit_arg);
+			hg_close(&handle);
+			clean_tmp();
+			break;
 	}
 
 	return 0;