Implement uniq.

1 files changed, 154 insertions, 0 deletions

diff --git a/toys/uniq.c b/toys/uniq.c
new file mode 100644
index 00000000..03913e71
--- /dev/null
+++ b/toys/uniq.c
@@ -0,0 +1,154 @@
+/* vi: set sw=4 ts=4:
+ *
+ * uniq.c - report or filter out repeated lines in a file
+ *
+ * Copyright 2012 Georgi Chorbadzhiyski <georgi@unixsol.org>
+ *
+ * See http://www.opengroup.org/onlinepubs/009695399/utilities/uniq.html
+
+USE_UNIQ(NEWTOY(uniq, "f#s#w#zicdu", TOYFLAG_BIN))
+
+config UNIQ
+	bool "uniq"
+	default y
+	help
+	  usage: uniq [-cduiz] [-w maxchars] [-f fields] [-s char] [input_file [output_file]]
+
+	  Report or filter out repeated lines in a file
+
+	  -c	show counts before each line
+	  -d	show only lines that are repeated
+	  -u	show only lines that are unique
+	  -i	ignore case when comparing lines
+	  -z	lines end with \0 not \n
+	  -w	compare maximum X chars per line
+	  -f	ignore first X fields
+	  -s	ignore first X chars
+*/
+
+#include "toys.h"
+
+DEFINE_GLOBALS(
+	long maxchars;
+	long nchars;
+	long nfields;
+	long repeats;
+)
+
+#define TT this.uniq
+
+#define FLAG_z 16
+#define FLAG_i 8
+#define FLAG_c 4
+#define FLAG_d 2
+#define FLAG_u 1
+
+static char *skip(char *str)
+{
+	int field = 0;
+	long nchars = TT.nchars;
+	long nfields = TT.nfields;
+	// Skip fields first
+	while (nfields && *str) {
+		if (isspace((unsigned char)*str)) {
+			if (field) {
+				field = 0;
+				nfields--;
+			}
+		} else if (!field) {
+			field = 1;
+		}
+		str++;
+	}
+	// Skip chars
+	while (nchars-- && *str)
+		str++;
+	return str;
+}
+
+static void print_line(FILE *f, char *line)
+{
+	if (TT.repeats == 0 && (toys.optflags & FLAG_d))
+		return;
+	if (TT.repeats > 0 && (toys.optflags & FLAG_u))
+		return;
+	if ((toys.optflags & FLAG_c)) {
+		fprintf(f, "%7lu %s", TT.repeats + 1, line);
+	} else {
+		fprintf(f, "%s", line);
+	}
+	if (toys.optflags & FLAG_z)
+		fprintf(f, "%c", '\0');
+}
+
+void uniq_main(void)
+{
+	FILE *infile = stdin;
+	FILE *outfile = stdout;
+	char *thisline = NULL;
+	char *prevline = NULL;
+	size_t thissize, prevsize = 0;
+	char *tmpline;
+	char eol = '\n';
+	size_t tmpsize;
+
+	if (toys.optc >= 1)
+		infile = xfopen(toys.optargs[0], "r");
+
+	if (toys.optc >= 2)
+		outfile = xfopen(toys.optargs[1], "w");
+
+	if (toys.optflags & FLAG_z)
+		eol = '\0';
+
+	// If first line can't be read
+	if (getdelim(&prevline, &prevsize, eol, infile) < 0)
+		return;
+
+	while (getdelim(&thisline, &thissize, eol, infile) > 0) {
+		int diff;
+		char *t1, *t2;
+
+		// If requested get the chosen fields + character offsets.
+		if (TT.nfields || TT.nchars) {
+			t1 = skip(thisline);
+			t2 = skip(prevline);
+		} else {
+			t1 = thisline;
+			t2 = prevline;
+		}
+
+		if (TT.maxchars == 0) {
+			diff = !(toys.optflags & FLAG_i)
+			        ? strcmp(t1, t2)
+			        : strcasecmp(t1, t2);
+		} else {
+			diff = !(toys.optflags & FLAG_i)
+			        ? strncmp(t1, t2, TT.maxchars)
+			        : strncasecmp(t1, t2, TT.maxchars);
+		}
+
+		if (diff == 0) { // same
+			TT.repeats++;
+		} else {
+			print_line(outfile, prevline);
+
+			TT.repeats = 0;
+
+			tmpline = prevline;
+			prevline = thisline;
+			thisline = tmpline;
+
+			tmpsize = prevsize;
+			prevsize = thissize;
+			thissize = tmpsize;
+		}
+	}
+
+	print_line(outfile, prevline);
+
+	if (CFG_TOYBOX_FREE) {
+		free(prevline);
+		free(thisline);
+	}
+}