From 8c274bb49758209f738af8175bb0dc441926404a Mon Sep 17 00:00:00 2001
From: Martin Mares <mj@ucw.cz>
Date: Tue, 24 Jul 2012 14:23:38 +0200
Subject: [PATCH] Cleaned up statistics

---
 TODO  |  1 -
 xsv.c | 38 ++++++++++++++++++++++++++------------
 2 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/TODO b/TODO
index 93a27da..e69de29 100644
--- a/TODO
+++ b/TODO
@@ -1 +0,0 @@
-- call ferror()
diff --git a/xsv.c b/xsv.c
index bd1f389..4ebe798 100644
--- a/xsv.c
+++ b/xsv.c
@@ -98,7 +98,7 @@ struct format {
 	int quiet;
 	int (*read_line)(struct format *fmt);
 	void (*write_line)(struct format *fmt);
-	int needs_two_passes;
+	int needs_stats;
 
 	// CSV backend:
 	int always_quote;
@@ -112,7 +112,6 @@ struct format {
 
 	// Temporary file backend:
 	FILE *tmp_file;
-	intarray_t column_widths;
 
 	// Table backend:
 	int table_sep;
@@ -192,6 +191,24 @@ static int field_chars(struct field *f)
 	return chars;
 }
 
+/*** Field statistics ***/
+
+static intarray_t column_widths;
+
+static void update_stats(void)
+{
+	for (int i = 0; i < fields_count(&in_fields); i++) {
+		struct field *f = fields_nth(&in_fields, i);
+		intarray_t *w = &column_widths;
+
+		while (i >= intarray_count(w))
+			*intarray_push(w) = 0;
+		int fw = field_chars(f);
+		if (*intarray_nth(w, i) < fw)
+			*intarray_nth(w, i) = fw;
+	}
+}
+
 /*** CSV/TSV back-end */
 
 static int csv_read(struct format *fmt)
@@ -364,7 +381,7 @@ static void table_write(struct format *fmt)
 			printf("%*s", fmt->table_sep, "");
 		struct field *f = fields_nth(&in_fields, i);
 		int fw = field_chars(f);
-		int cw = *intarray_nth(&in_format->column_widths, i);
+		int cw = *intarray_nth(&column_widths, i);
 		if (fw > cw) {
 			warn(fmt, "Internal error: Wrongly calculated column width (%d > %d)", fw, cw);
 			cw = fw;
@@ -433,13 +450,6 @@ static void tmp_write(struct format *fmt)
 		unsigned char *p = line_nth(&in_line, f->start_pos);
 		for (int j = 0; j < f->len; j++)
 			putc_unlocked(*p++, tf);
-
-		intarray_t *w = &fmt->column_widths;
-		while (i >= intarray_count(w))
-			*intarray_push(w) = 0;
-		int fw = field_chars(f);
-		if (*intarray_nth(w, i) < fw)
-			*intarray_nth(w, i) = fw;
 	}
 	putc_unlocked(0xff, tf);
 
@@ -534,6 +544,8 @@ static void one_pass(void)
 		fields_reset(&out_fields);
 		select_fields();
 
+		if (out_format->needs_stats)
+			update_stats();
 		out_format->write_line(out_format);
 		if (ferror_unlocked(stdout))
 			die("I/O error when writing standard input");
@@ -553,12 +565,14 @@ static void two_pass(void)
 	out_format->read_line = tmp_read;
 	out_format->write_line = tmp_write;
 	out_format->tmp_file = tmpfile();
+	out_format->needs_stats = final_format->needs_stats;
 	one_pass();
 
 	// Pass 2: Set up reader of intermediate format
 	in_format = out_format;
 	rewind(in_format->tmp_file);
 	out_format = final_format;
+	out_format->needs_stats = 0;
 	one_pass();
 	fclose(in_format->tmp_file);
 }
@@ -659,7 +673,7 @@ static void set_format(int format_id)
 			break;
 		case FORM_TABLE:
 			f->write_line = table_write;
-			f->needs_two_passes = 1;
+			f->needs_stats = 1;
 			f->table_sep = 2;
 			break;
 	}
@@ -752,7 +766,7 @@ int main(int argc, char **argv)
 	}
 	finish_parse_selectors();
 
-	if (out_format->needs_two_passes)
+	if (out_format->needs_stats)
 		two_pass();
 	else
 		one_pass();
-- 
2.39.2