[pacman-dev] [PATCH 5/6] Table formatted output functions

[Jakob Gruber]

table_display takes a list of lists of strings (representing the table
cells) and displays them formatted as a table.
The exact format depends on the longest string in each column.

Signed-off-by: Jakob Gruber <jakob.gruber at gmail.com>
---
 src/pacman/util.c |  108 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/pacman/util.h |    1 +
 2 files changed, 109 insertions(+), 0 deletions(-)

diff --git a/src/pacman/util.c b/src/pacman/util.c
index 85d2d8c..8f7b5e5 100644
--- a/src/pacman/util.c
+++ b/src/pacman/util.c
@@ -435,6 +435,114 @@ void string_display(const char *title, const char *string)
 	printf("\n");
 }
 
+static void table_print_line(const alpm_list_t *line,
+															const alpm_list_t *formats)
+{
+	const alpm_list_t *curformat = formats;
+	const alpm_list_t *curcell = line;
+
+	while (curcell && curformat) {
+		printf(alpm_list_getdata(curformat), alpm_list_getdata(curcell));
+		curcell = alpm_list_next(curcell);
+		curformat = alpm_list_next(curformat);
+	}
+
+	printf("\n");
+}
+
+/* creates a format string by checking max cell lengths in rows */
+static alpm_list_t *table_create_format(const alpm_list_t *rows)
+{
+	alpm_list_t *format, *curformat;
+	const alpm_list_t *currow, *curcell;
+	char *str, *formatstr;
+	const int padding = 2;
+	int cols, neededcols = 0;
+
+	/* initial format list element */
+	format = alpm_list_add(NULL, NULL);
+
+	/* go through each cell and store the longest string for each
+	 * column in the format list */
+	currow = rows;
+	while(currow != NULL) {
+
+		/* starting on new row, reset format pointer to first column */
+		curformat = format;
+
+		/* loop through all row cells and update format pointer if necessary */
+		curcell = alpm_list_getdata(currow);
+		while(curcell != NULL) {
+			if(curformat == NULL) {
+				curformat = alpm_list_last(alpm_list_add(format, NULL));
+			}
+
+			str = alpm_list_getdata(curcell);
+			if(curformat->data == NULL ||
+					strlen(str) > strlen(alpm_list_getdata(curformat)))
+				curformat->data = str;
+
+			curformat = alpm_list_next(curformat);
+			curcell = alpm_list_next(curcell);
+		}
+
+		currow = alpm_list_next(currow);
+	}
+
+	/* now use the column width info to generate format strings */
+	curformat = format;
+	while(curformat != NULL) {
+		cols = strlen(curformat->data) + padding;
+		neededcols += cols;
+
+		str = (alpm_list_next(curformat) != NULL) ? "%%-%ds" : "%%%ds";
+		pm_asprintf(&formatstr, str, cols);
+
+		curformat->data = formatstr;
+		curformat = alpm_list_next(curformat);
+	}
+
+	/* return NULL if terminal is not wide enough */
+	if(neededcols > getcols()) {
+		FREELIST(format);
+		return NULL;
+	}
+
+	return format;
+}
+
+/** Displays the list in table format
+ *
+ * @param title the tables title
+ * @param rows  the rows to display as a list of lists of strings. the outer
+ * 							list represents the rows, the inner list the cells (= columns)
+ *
+ * @return -1 if not enough terminal cols available, else 0
+ */
+int table_display(const char *title, const alpm_list_t *rows)
+{
+	alpm_list_t *i, *formats;
+
+	if(rows == NULL)
+		return 0;
+
+	formats = table_create_format(rows);
+	if(formats == NULL) {
+		return -1;
+	}
+
+	if(title != NULL) {
+		printf("%s\n\n", title);
+	}
+
+	for(i = alpm_list_first(rows); i; i = alpm_list_next(i)) {
+		table_print_line(alpm_list_getdata(i), formats);
+	}
+
+	FREELIST(formats);
+	return 0;
+}
+
 void list_display(const char *title, const alpm_list_t *list)
 {
 	const alpm_list_t *i;
diff --git a/src/pacman/util.h b/src/pacman/util.h
index ed03c13..494becf 100644
--- a/src/pacman/util.h
+++ b/src/pacman/util.h
@@ -56,6 +56,7 @@ char *size_to_human_string_mb(off_t bytes);
 char *size_to_human_string_kb(off_t bytes);
 char *size_to_human_string_short(off_t bytes);
 void string_display(const char *title, const char *string);
+int table_display(const char *title, const alpm_list_t *rows);
 void list_display(const char *title, const alpm_list_t *list);
 void list_display_linebreak(const char *title, const alpm_list_t *list);
 void display_targets(const alpm_list_t *pkgs, int install);
-- 
1.7.4.1