6 files changed, 240 insertions, 123 deletions

diff --git a/libsmartcols/samples/Makemodule.am b/libsmartcols/samples/Makemodule.am
index c0130b9..b192eba 100644
--- a/libsmartcols/samples/Makemodule.am
+++ b/libsmartcols/samples/Makemodule.am
@@ -4,13 +4,13 @@ check_PROGRAMS += \
 	sample-scols-title \
 	sample-scols-wrap \
 	sample-scols-continuous \
+	sample-scols-continuous-json \
 	sample-scols-fromfile \
 	sample-scols-grouping-simple \
 	sample-scols-grouping-overlay \
 	sample-scols-maxout
 
-sample_scols_cflags = $(AM_CFLAGS) $(NO_UNUSED_WARN_CFLAGS) \
-                      -I$(ul_libsmartcols_incdir)
+sample_scols_cflags = $(AM_CFLAGS) -I$(ul_libsmartcols_incdir)
 sample_scols_ldadd = libsmartcols.la $(LDADD)
 
 if HAVE_OPENAT
@@ -36,6 +36,10 @@ sample_scols_continuous_SOURCES = libsmartcols/samples/continuous.c
 sample_scols_continuous_LDADD = $(sample_scols_ldadd) libcommon.la
 sample_scols_continuous_CFLAGS = $(sample_scols_cflags)
 
+sample_scols_continuous_json_SOURCES = libsmartcols/samples/continuous-json.c
+sample_scols_continuous_json_LDADD = $(sample_scols_ldadd) libcommon.la
+sample_scols_continuous_json_CFLAGS = $(sample_scols_cflags)
+
 sample_scols_maxout_SOURCES = libsmartcols/samples/maxout.c
 sample_scols_maxout_LDADD = $(sample_scols_ldadd)
 sample_scols_maxout_CFLAGS = $(sample_scols_cflags)
diff --git a/libsmartcols/samples/continuous-json.c b/libsmartcols/samples/continuous-json.c
new file mode 100644
index 0000000..ae1f405
--- /dev/null
+++ b/libsmartcols/samples/continuous-json.c
@@ -0,0 +1,80 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
+ * Copyright (C) 2016 Karel Zak <kzak@redhat.com>
+ * Copyright (C) 2023 Thomas Weißschuh <thomas@t-8ch.de>
+ */
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+
+#include "c.h"
+#include "xalloc.h"
+
+#include "libsmartcols.h"
+
+/* add columns to the @tb */
+static void setup_columns(struct libscols_table *tb)
+{
+	scols_table_enable_maxout(tb, 1);
+	if (!scols_table_new_column(tb, "COUNT", 0.1, SCOLS_FL_RIGHT))
+		goto fail;
+	if (!scols_table_new_column(tb, "TEXT", 0.9, 0))
+		goto fail;
+	return;
+fail:
+	scols_unref_table(tb);
+	err(EXIT_FAILURE, "failed to create output columns");
+}
+
+static struct libscols_line *add_line(struct libscols_table *tb, int i)
+{
+	char *p;
+	struct libscols_line *ln = scols_table_new_line(tb, NULL);
+
+	if (!ln)
+		err(EXIT_FAILURE, "failed to create output line");
+
+	xasprintf(&p, "%d", i);
+	if (scols_line_refer_data(ln, 0, p))
+		goto fail;
+
+	xasprintf(&p, "text%d", i);
+	if (scols_line_refer_data(ln, 1, p))
+		goto fail;
+
+	return ln;
+fail:
+	scols_unref_table(tb);
+	err(EXIT_FAILURE, "failed to create output line");
+}
+
+int main(void)
+{
+	struct libscols_table *tb;
+	size_t i;
+
+	scols_init_debug(0);
+
+	tb = scols_new_table();
+	if (!tb)
+		err(EXIT_FAILURE, "failed to create output table");
+	scols_table_enable_json(tb, 1);
+
+	setup_columns(tb);
+
+	for (i = 0; i < 10; i++) {
+		struct libscols_line *line;
+
+		line = add_line(tb, i);
+
+		/* print the line */
+		scols_table_print_range(tb, line, NULL);
+
+		fflush(scols_table_get_stream(tb));
+	}
+
+	scols_unref_table(tb);
+	return EXIT_SUCCESS;
+}
diff --git a/libsmartcols/samples/continuous.c b/libsmartcols/samples/continuous.c
index 6bdba6e..432b027 100644
--- a/libsmartcols/samples/continuous.c
+++ b/libsmartcols/samples/continuous.c
@@ -65,7 +65,7 @@ fail:
 	err(EXIT_FAILURE, "failed to create output line");
 }
 
-int main(int argc, char *argv[])
+int main(void)
 {
 	struct libscols_table *tb;
 	size_t i;
@@ -85,7 +85,7 @@ int main(int argc, char *argv[])
 		struct libscols_line *line;
 		struct timeval now;
 		int done = 0;
-		char *timecell = xmalloc( timecellsz );
+		char *timecell = xcalloc(1, timecellsz );
 
 		line = add_line(tb, i);
 
diff --git a/libsmartcols/samples/fromfile.c b/libsmartcols/samples/fromfile.c
index 0fdc929..cf77cc4 100644
--- a/libsmartcols/samples/fromfile.c
+++ b/libsmartcols/samples/fromfile.c
@@ -18,136 +18,63 @@
 #include "strutils.h"
 #include "xalloc.h"
 #include "optutils.h"
+#include "mangle.h"
+#include "path.h"
 
 #include "libsmartcols.h"
 
-struct column_flag {
-	const char *name;
-	int mask;
-};
-
-static const struct column_flag flags[] = {
-	{ "trunc",	SCOLS_FL_TRUNC },
-	{ "tree",	SCOLS_FL_TREE },
-	{ "right",	SCOLS_FL_RIGHT },
-	{ "strictwidth",SCOLS_FL_STRICTWIDTH },
-	{ "noextremes", SCOLS_FL_NOEXTREMES },
-	{ "hidden",	SCOLS_FL_HIDDEN },
-	{ "wrap",	SCOLS_FL_WRAP },
-	{ "wrapnl",	SCOLS_FL_WRAP },
-	{ "none",	0 }
-};
-
-static long name_to_flag(const char *name, size_t namesz)
+static struct libscols_column *parse_column(const char *path)
 {
-	size_t i;
+	char buf[BUFSIZ];
+	struct libscols_column *cl;
 
-	for (i = 0; i < ARRAY_SIZE(flags); i++) {
-		const char *cn = flags[i].name;
+	if (ul_path_read_buffer(NULL, buf, sizeof(buf), path) < 0)
+		err(EXIT_FAILURE, "failed to read column: %s", path);
 
-		if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))
-			return flags[i].mask;
-	}
-	warnx("unknown flag: %s", name);
-	return -1;
-}
-
-static int parse_column_flags(char *str)
-{
-	unsigned long num_flags = 0;
-
-	if (string_to_bitmask(str, &num_flags, name_to_flag))
-		err(EXIT_FAILURE, "failed to parse column flags");
-
-	return num_flags;
-}
-
-static struct libscols_column *parse_column(FILE *f)
-{
-	size_t len = 0;
-	char *line = NULL;
-	int nlines = 0;
+	cl = scols_new_column();
+	if (!cl)
+		err(EXIT_FAILURE, "failed to allocate column");
 
-	struct libscols_column *cl = NULL;
+	if (scols_column_set_properties(cl, buf) != 0)
+		err(EXIT_FAILURE, "failed to set column properties");
 
-	while (getline(&line, &len, f) != -1) {
-
-		char *p = strrchr(line, '\n');
-		if (p)
-			*p = '\0';
-
-		switch (nlines) {
-		case 0: /* NAME */
-			cl = scols_new_column();
-			if (!cl)
-				goto fail;
-			if (scols_column_set_name(cl, line) != 0)
-				goto fail;
-			break;
-
-		case 1: /* WIDTH-HINT */
-		{
-			double whint = strtod_or_err(line, "failed to parse column whint");
-			if (scols_column_set_whint(cl, whint))
-				goto fail;
-			break;
-		}
-		case 2: /* FLAGS */
-		{
-			int num_flags = parse_column_flags(line);
-			if (scols_column_set_flags(cl, num_flags))
-				goto fail;
-			if (strcmp(line, "wrapnl") == 0) {
-				scols_column_set_wrapfunc(cl,
-						scols_wrapnl_chunksize,
-						scols_wrapnl_nextchunk,
-						NULL);
-				scols_column_set_safechars(cl, "\n");
-			}
-			break;
-		}
-		case 3: /* COLOR */
-			if (scols_column_set_color(cl, line))
-				goto fail;
-			break;
-		default:
-			break;
-		}
-
-		nlines++;
-	}
-
-	free(line);
 	return cl;
-fail:
-	free(line);
-	scols_unref_column(cl);
-	return NULL;
 }
 
 static int parse_column_data(FILE *f, struct libscols_table *tb, int col)
 {
 	size_t len = 0, nlines = 0;
-	int i;
-	char *str = NULL;
+	ssize_t i;
+	char *str = NULL, *p;
 
 	while ((i = getline(&str, &len, f)) != -1) {
-
 		struct libscols_line *ln;
-		char *p = strrchr(str, '\n');
-		if (p)
-			*p = '\0';
-
-		while ((p = strrchr(str, '\\')) && *(p + 1) == 'n') {
-			*p = '\n';
-			memmove(p + 1, p + 2, i - (p + 2 - str));
-		}
+		int rc = 0;
 
 		ln = scols_table_get_line(tb, nlines++);
 		if (!ln)
 			break;
 
-		if (*str && scols_line_set_data(ln, col, str) != 0)
+		p = strrchr(str, '\n');
+		if (p)
+			*p = '\0';
+		if (!*str)
+			continue;
+
+		/* convert \x?? to real bytes */
+		if (strstr(str, "\\x")) {
+			struct libscols_cell *ce = scols_line_get_cell(ln, col);
+			size_t sz = i + 1;
+			char *buf = xcalloc(1, sz);
+
+			sz = unhexmangle_to_buffer(str, buf, sz);
+			if (sz)
+				rc = scols_cell_refer_memory(ce, buf, sz);
+			else
+				free(buf);
+		} else
+			rc = scols_line_set_data(ln, col, str);
+		if (rc)
 			err(EXIT_FAILURE, "failed to add output data");
 	}
 
@@ -193,6 +120,83 @@ static void compose_tree(struct libscols_table *tb, int parent_col, int id_col)
 	scols_free_iter(itr);
 }
 
+static struct libscols_filter *init_filter(
+			struct libscols_table *tb,
+			const char *query, int dump)
+{
+	struct libscols_iter *itr;
+	struct libscols_filter *f = scols_new_filter(NULL);
+	const char *name = NULL;
+	int rc = 0;
+
+	if (!f)
+		err(EXIT_FAILURE, "failed to allocate filter");
+	if (scols_filter_parse_string(f, query) != 0) {
+		warnx("failed to parse filter: %s", scols_filter_get_errmsg(f));
+		scols_unref_filter(f);
+		return NULL;
+	}
+
+	itr = scols_new_iter(SCOLS_ITER_FORWARD);
+	if (!itr)
+		err(EXIT_FAILURE, "failed to allocate iterator");
+
+	while (scols_filter_next_holder(f, itr, &name, 0) == 0) {
+		struct libscols_column *col;
+
+		col = scols_table_get_column_by_name(tb, name);
+		if (!col) {
+			warnx("unknown column '%s' in filter", name);
+			rc++;
+			continue;
+		}
+		scols_filter_assign_column(f, itr, name, col);
+	}
+
+	scols_free_iter(itr);
+	if (dump && f)
+		scols_dump_filter(f, stdout);
+	if (rc) {
+		scols_unref_filter(f);
+		errx(EXIT_FAILURE, "failed to initialize filter");
+	}
+
+	return f;
+}
+
+/* Note: This is a simple (naive) way to use the filter, employed here for
+ * testing functionality.
+ *
+ * A more effective approach to using the filter is demonstrated in lsblk.c,
+ * where data manipulation is divided into two steps. The initial step prepares
+ * only the data necessary for evaluating the filter, and the remaining data is
+ * gathered later, only if necessary.
+ */
+static void apply_filter(struct libscols_table *tb, struct libscols_filter *fltr)
+{
+	struct libscols_iter *itr = scols_new_iter(SCOLS_ITER_FORWARD);
+	struct libscols_line *ln;
+
+	if (!itr)
+		err(EXIT_FAILURE, "failed to allocate iterator");
+
+	while (scols_table_next_line(tb, itr, &ln) == 0) {
+		int status = 0;
+
+		if (scols_line_apply_filter(ln, fltr, &status) != 0)
+			err(EXIT_FAILURE, "failed to apply filter");
+		if (status == 0) {
+			struct libscols_line *x = scols_line_get_parent(ln);
+
+			if (x)
+				scols_line_remove_child(x, ln);
+			scols_table_remove_line(tb, ln);
+			ln = NULL;
+		}
+	}
+
+	scols_free_iter(itr);
+}
 
 static void __attribute__((__noreturn__)) usage(void)
 {
@@ -211,6 +215,7 @@ static void __attribute__((__noreturn__)) usage(void)
 	fputs(" -w, --width <num>              hardcode terminal width\n", out);
 	fputs(" -p, --tree-parent-column <n>   parent column\n", out);
 	fputs(" -i, --tree-id-column <n>       id column\n", out);
+	fputs(" -Q, --filter <expr>            filter\n", out);
 	fputs(" -h, --help                     this help\n", out);
 	fputs("\n", out);
 
@@ -220,8 +225,11 @@ static void __attribute__((__noreturn__)) usage(void)
 int main(int argc, char *argv[])
 {
 	struct libscols_table *tb;
-	int c, n, nlines = 0;
+	int c, n, nlines = 0, rc;
 	int parent_col = -1, id_col = -1;
+	int fltr_dump = 0;
+	const char *fltr_str = NULL;
+	struct libscols_filter *fltr = NULL;
 
 	static const struct option longopts[] = {
 		{ "maxout", 0, NULL, 'm' },
@@ -235,6 +243,8 @@ int main(int argc, char *argv[])
 		{ "raw",    0, NULL, 'r' },
 		{ "export", 0, NULL, 'E' },
 		{ "colsep",  1, NULL, 'C' },
+		{ "filter", 1, NULL, 'Q' },
+		{ "filter-dump", 0, NULL, 'd' },
 		{ "help",   0, NULL, 'h' },
 		{ NULL, 0, NULL, 0 },
 	};
@@ -253,25 +263,23 @@ int main(int argc, char *argv[])
 	if (!tb)
 		err(EXIT_FAILURE, "failed to create output table");
 
-	while((c = getopt_long(argc, argv, "hCc:Ei:JMmn:p:rw:", longopts, NULL)) != -1) {
+	while((c = getopt_long(argc, argv, "hCc:dEi:JMmn:p:Q:rw:", longopts, NULL)) != -1) {
 
 		err_exclusive_options(c, longopts, excl, excl_st);
 
 		switch(c) {
 		case 'c': /* add column from file */
 		{
-			struct libscols_column *cl;
-			FILE *f = fopen(optarg, "r");
+			struct libscols_column *cl = parse_column(optarg);
 
-			if (!f)
-				err(EXIT_FAILURE, "%s: open failed", optarg);
-			cl = parse_column(f);
 			if (cl && scols_table_add_column(tb, cl))
 				err(EXIT_FAILURE, "%s: failed to add column", optarg);
 			scols_unref_column(cl);
-			fclose(f);
 			break;
 		}
+		case 'd':
+			fltr_dump = 1;
+			break;
 		case 'p':
 			parent_col = strtou32_or_err(optarg, "failed to parse tree PARENT column");
 			break;
@@ -300,6 +308,9 @@ int main(int argc, char *argv[])
 		case 'n':
 			nlines = strtou32_or_err(optarg, "failed to parse number of lines");
 			break;
+		case 'Q':
+			fltr_str = optarg;
+			break;
 		case 'w':
 			scols_table_set_termforce(tb, SCOLS_TERMFORCE_ALWAYS);
 			scols_table_set_termwidth(tb, strtou32_or_err(optarg, "failed to parse terminal width"));
@@ -323,6 +334,14 @@ int main(int argc, char *argv[])
 		scols_unref_line(ln);
 	}
 
+	if (fltr_str) {
+		fltr = init_filter(tb, fltr_str, fltr_dump);
+		if (!fltr) {
+			rc = EXIT_FAILURE;
+			goto done;
+		}
+	}
+
 	n = 0;
 
 	while (optind < argc) {
@@ -341,7 +360,13 @@ int main(int argc, char *argv[])
 
 	scols_table_enable_colors(tb, isatty(STDOUT_FILENO));
 
+	if (fltr)
+		apply_filter(tb, fltr);
+
 	scols_print_table(tb);
+	rc = EXIT_SUCCESS;
+done:
+	scols_unref_filter(fltr);
 	scols_unref_table(tb);
-	return EXIT_SUCCESS;
+	return rc;
 }
diff --git a/libsmartcols/samples/maxout.c b/libsmartcols/samples/maxout.c
index 20c6424..a867697 100644
--- a/libsmartcols/samples/maxout.c
+++ b/libsmartcols/samples/maxout.c
@@ -19,7 +19,7 @@
 
 enum { COL_LEFT, COL_FOO, COL_RIGHT };
 
-int main(int argc, char *argv[])
+int main(void)
 {
 	struct libscols_table *tb;
 	int rc = -1, nlines = 3;
diff --git a/libsmartcols/samples/wrap.c b/libsmartcols/samples/wrap.c
index 795bef7..8368304 100644
--- a/libsmartcols/samples/wrap.c
+++ b/libsmartcols/samples/wrap.c
@@ -92,7 +92,15 @@ int main(int argc, char *argv[])
 	if (!tb)
 		err(EXIT_FAILURE, "failed to create output table");
 
-	scols_table_enable_colors(tb, isatty(STDOUT_FILENO));
+	if (argc > 1 && strcmp(argv[1], "--export") == 0)
+		scols_table_enable_export(tb, 1);
+	else if (argc > 1 && strcmp(argv[1], "--raw") == 0)
+		scols_table_enable_raw(tb, 1);
+	else if (argc > 1 && strcmp(argv[1], "--json") == 0)
+		scols_table_enable_json(tb, 1);
+	else
+		scols_table_enable_colors(tb, isatty(STDOUT_FILENO));
+
 	setup_columns(tb);
 
 	ln = add_line(tb, NULL, "A");