Refactor option-parser table printing code for reuse

Signed-off-by: Jim Ramsay <i.am@jimramsay.com>

include/table-printer.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2023 Jim Ramsay
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdio.h>
+
+struct table_printer{
+	FILE* stream;
+	int max_width;
+	int left_indent;
+	int left_width;
+	int column_offset;
+};
+
+// Sets default values for every subsequent table_printer_new (Optional: defaults to 80/4/8)
+void table_printer_set_defaults(int max_width, int left_indent,
+		int column_offset);
+
+void table_printer_init(struct table_printer* self, FILE* stream,
+		int left_width);
+
+void table_printer_print_line(struct table_printer* self, const char* left_text,
+		const char* right_text);
+
+void table_printer_print_fmtline(struct table_printer* self,
+		const char* right_text,
+		const char* left_format, ...);
+
+int table_printer_reflow_text(char* dst, int dst_size, const char* src,
+		int width);
+
+void table_printer_indent_and_reflow_text(FILE* stream, const char* src,
+		int width, int first_line_indent, int subsequent_indent);
+

meson.build

@@ -99,6 +99,7 @@ sources = [
 	'src/ctl-server.c',
 	'src/ctl-commands.c',
 	'src/option-parser.c',
+        'src/table-printer.c',
 ]
 
 dependencies = [
@@ -123,6 +124,7 @@ ctlsources = [
 	'src/ctl-commands.c',
 	'src/strlcpy.c',
 	'src/option-parser.c',
+        'src/table-printer.c',
 ]
 
 ctldependencies = [

src/option-parser.c

@@ -16,6 +16,7 @@
 
 #include "option-parser.h"
 #include "strlcpy.h"
+#include "table-printer.h"
 
 #include <stdio.h>
 #include <string.h>
@@ -72,82 +73,35 @@ static int get_left_col_width(const struct wv_option* opts, int n)
 	return max_width;
 }
 
-static void reflow_text(char* dst, const char* src, int width)
+static void format_option(struct table_printer* printer, const struct wv_option* opt)
-{
-	int line_len = 0;
-	int last_space_pos = 0;
-	
-	int dst_len = 0;
-	int i = 0; 
-
-	while (src[i]) {
-		char c = src[i];
-
-		if (line_len > width) {
-			assert(last_space_pos > 0);
-
-			dst_len -= i - last_space_pos;
-			dst[dst_len++] = '\n';
-			i = last_space_pos + 1;
-			line_len = 0;
-			continue;
-		}
-
-		if (c == ' ')
-			last_space_pos = i;
-
-		dst[dst_len++] = c;
-		++i;
-		++line_len;
-	}
-
-	dst[dst_len] = '\0';
-}
-
-static void format_option(const struct wv_option* opt, int left_col_width,
-		FILE* stream)
 {
 	if (!opt->help)
 		return;
 
-	int n_chars = fprintf(stream, "    ");
+	int n_chars = 0;
+	char buf[64];
 	if (opt->short_opt)
-		n_chars += fprintf(stream, "-%c", opt->short_opt);
+		n_chars += snprintf(buf + n_chars, sizeof(buf) - n_chars,
+				"-%c", opt->short_opt);
 	if (opt->long_opt)
-		n_chars += fprintf(stream, "%s--%s",
+		n_chars += snprintf(buf + n_chars, sizeof(buf) - n_chars,
-				opt->short_opt ? "," : "", opt->long_opt);
+				"%s--%s", opt->short_opt ? "," : "",
+				opt->long_opt);
 	if (opt->schema)
-		n_chars += fprintf(stream, "%s%s",
+		n_chars += snprintf(buf + n_chars, sizeof(buf) - n_chars,
-				opt->long_opt ? "=" : "", opt->schema);
+				"%s%s", opt->long_opt ? "=" : "", opt->schema);
 
-	n_chars += fprintf(stream, "%*s", left_col_width - n_chars + 8, "");
+	table_printer_print_line(printer, buf, opt->help);
-
-	int right_col_width = 80 - 8 - left_col_width;
-	assert(right_col_width >= 0);
-
-	char help[256];
-	reflow_text(help, opt->help, right_col_width);
-
-	char* line = strtok(help, "\n");
-	fprintf(stream, "%s\n", line);
-
-	while (true) {
-		line = strtok(NULL, "\n");
-		if (!line)
-			break;
-
-		fprintf(stream, "%*s%s\n", left_col_width + 8, "", line);
-	}
 }
 
 void option_parser_print_options(struct option_parser* self, FILE* stream)
 {
 	fprintf(stream, "%s:\n", self->name);
 	int left_col_width = get_left_col_width(self->options, self->n_opts);
-
+	struct table_printer printer;
-	for (int i = 0; i < self->n_opts; ++i) {
+	table_printer_init(&printer, stream, left_col_width);
-		format_option(&self->options[i], left_col_width, stream);
+	for (int i = 0; i < self->n_opts; ++i)
-	}
+		format_option(&printer, &self->options[i]);
 }
 
 static const struct wv_option* find_long_option(

src/table-printer.c

@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) 2023 Andri Yngvason
+ * Copyright (c) 2023 Jim Ramsay
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "table-printer.h"
+
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <string.h>
+#include <assert.h>
+
+static struct table_printer defaults = {
+	.max_width = 80,
+	.left_indent = 4,
+	.column_offset = 8,
+	.stream = NULL,
+	.left_width = 0,
+};
+
+void table_printer_set_defaults(int max_width, int left_indent,
+		int column_offset)
+{
+	defaults.max_width = max_width;
+	defaults.left_indent = left_indent;
+	defaults.column_offset = column_offset;
+}
+
+void table_printer_init(struct table_printer* self, FILE* stream,
+		int left_width)
+{
+	memcpy(self, &defaults, sizeof(*self));
+	self->stream = stream;
+	self->left_width = left_width;
+}
+
+int table_printer_reflow_text(char* dst, int dst_size, const char* src,
+		int width)
+{
+	int line_len = 0;
+	int last_space_pos = 0;
+
+	int dst_len = 0;
+	int i = 0;
+
+	while (true) {
+		char c = src[i];
+		if (line_len > width) {
+			// first word > width
+			assert(last_space_pos > 0);
+			// subsequent word > width
+			assert(dst[last_space_pos] != '\n');
+
+			dst_len -= i - last_space_pos;
+			dst[dst_len++] = '\n';
+			i = last_space_pos + 1;
+			line_len = 0;
+			continue;
+		}
+		if (!c)
+			break;
+
+		if (c == ' ')
+			last_space_pos = i;
+		dst[dst_len++] = c;
+		assert(dst_len < dst_size);
+		++line_len;
+		++i;
+	}
+
+	dst[dst_len] = '\0';
+	return dst_len;
+}
+
+void table_printer_indent_and_reflow_text(FILE* stream, const char* src,
+		int width, int first_line_indent, int subsequent_indent)
+{
+	char buffer[256];
+	table_printer_reflow_text(buffer, sizeof(buffer), src, width);
+
+	char* line = strtok(buffer, "\n");
+	fprintf(stream, "%*s%s\n", first_line_indent, "", line);
+
+	while (true) {
+		line = strtok(NULL, "\n");
+		if (!line)
+			break;
+
+		fprintf(stream, "%*s%s\n", subsequent_indent, "", line);
+	}
+}
+
+void table_printer_print_line(struct table_printer* self, const char* left_text,
+		const char* right_text)
+{
+	fprintf(self->stream, "%*s", self->left_indent, "");
+	int field_len = fprintf(self->stream, "%s", left_text);
+	fprintf(self->stream, "%*s", self->left_width - field_len + self->column_offset, "");
+	int column_indent = self->left_indent + self->left_width + self->column_offset;
+	int column_width = self->max_width - column_indent;
+	table_printer_indent_and_reflow_text(self->stream,
+			right_text,
+			column_width, 0, column_indent);
+}
+
+void table_printer_print_fmtline(struct table_printer* self,
+		const char* right_text,
+		const char* left_format, ...)
+{
+	char buf[64];
+	va_list args;
+	va_start(args, left_format);
+	vsnprintf(buf, sizeof(buf), left_format, args);
+	va_end(args);
+	table_printer_print_line(self, buf, right_text);
+}
+

test/meson.build

@@ -1,10 +1,18 @@
-option_parser = executable('option-parser',
+test('table-printer', executable('table-printer',
+	[
+		'table-printer-test.c',
+		'../src/table-printer.c',
+	],
+	include_directories: inc,
+	dependencies: [ ],
+))
+test('option-parser', executable('option-parser',
 	[
 		'option-parser-test.c',
 		'../src/option-parser.c',
+		'../src/table-printer.c',
 		'../src/strlcpy.c',
 	],
 	include_directories: inc,
 	dependencies: [ ],
-)
+))
-test('option-parser', option_parser)

test/table-printer-test.c

@@ -0,0 +1,145 @@
+#include "tst.h"
+#include "table-printer.h"
+#include <stdlib.h>
+
+static int test_reflow_text(void)
+{
+	char buf[20];
+	const char* src = "one two three four";
+	int len;
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 20);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one two three four", buf);
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 18);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one two three four", buf);
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 17);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one two three\nfour", buf);
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 10);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one two\nthree four", buf);
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 8);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one two\nthree\nfour", buf);
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 7);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one two\nthree\nfour", buf);
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 6);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one\ntwo\nthree\nfour", buf);
+
+	len = table_printer_reflow_text(buf, sizeof(buf), src, 5);
+	ASSERT_INT_EQ(18, len);
+	ASSERT_STR_EQ("one\ntwo\nthree\nfour", buf);
+
+	// width <= 4 cause aborts (if any word length > width)
+
+	return 0;
+}
+
+static int test_indent_and_reflow(void)
+{
+	size_t len;
+	char* buf;
+	FILE* stream;
+
+	stream = open_memstream(&buf, &len);
+	table_printer_indent_and_reflow_text(stream, "one two three four", 7, 2, 4);
+	fclose(stream);
+	// strlen(src)=18 + first=2 + subsequent=(2x4) + newline=1
+	ASSERT_INT_EQ(29, len);
+	ASSERT_STR_EQ("  one two\n    three\n    four\n", buf);
+	free(buf);
+	return 0;
+}
+
+static int test_defaults(void)
+{
+	struct table_printer one;
+	table_printer_init(&one, stdout, 1);
+	table_printer_set_defaults(20, 2, 2);
+	struct table_printer two;
+	table_printer_init(&two, stderr, 2);
+	ASSERT_INT_EQ(80, one.max_width);
+	ASSERT_INT_EQ(4, one.left_indent);
+	ASSERT_INT_EQ(8, one.column_offset);
+	ASSERT_INT_EQ(1, one.left_width);
+	ASSERT_PTR_EQ(stdout, one.stream);
+	ASSERT_INT_EQ(20, two.max_width);
+	ASSERT_INT_EQ(2, two.left_indent);
+	ASSERT_INT_EQ(2, two.column_offset);
+	ASSERT_INT_EQ(2, two.left_width);
+	ASSERT_PTR_EQ(stderr, two.stream);
+	return 0;
+}
+
+static int test_print_line(void)
+{
+	size_t len;
+	char* buf;
+	struct table_printer printer = {
+		.max_width = 20,
+		.left_indent = 2,
+		.left_width = 6,
+		.column_offset = 2,
+	};
+
+	printer.stream = open_memstream(&buf, &len);
+	table_printer_print_line(&printer, "left", "right");
+	fclose(printer.stream);
+	ASSERT_STR_EQ("  left    right\n", buf);
+	free(buf);
+
+	printer.stream = open_memstream(&buf, &len);
+	table_printer_print_line(&printer, "left", "right side will wrap");
+	fclose(printer.stream);
+	ASSERT_STR_EQ("  left    right side\n"
+		      "          will wrap\n", buf);
+	free(buf);
+	return 0;
+}
+
+static int test_print_fmtline(void)
+{
+	size_t len;
+	char* buf;
+	struct table_printer printer = {
+		.max_width = 20,
+		.left_indent = 2,
+		.left_width = 6,
+		.column_offset = 2,
+	};
+
+	printer.stream = open_memstream(&buf, &len);
+	table_printer_print_fmtline(&printer, "right", "left");
+	fclose(printer.stream);
+	ASSERT_STR_EQ("  left    right\n", buf);
+	free(buf);
+
+	printer.stream = open_memstream(&buf, &len);
+	table_printer_print_fmtline(&printer, "right side will wrap", "left%d", 2);
+	fclose(printer.stream);
+	ASSERT_STR_EQ("  left2   right side\n"
+		      "          will wrap\n", buf);
+	free(buf);
+	return 0;
+}
+
+int main()
+{
+	int r = 0;
+	RUN_TEST(test_reflow_text);
+	RUN_TEST(test_indent_and_reflow);
+	RUN_TEST(test_defaults);
+	RUN_TEST(test_print_line);
+	RUN_TEST(test_print_fmtline);
+	return r;
+}