[hackers] [sbase] uniq: add support for writing output files || Tai Chi Minh Ralph Eastwood

[git]

commit c15103a0c8440f5c645b435bf2c2c42e605290b1
Author: Tai Chi Minh Ralph Eastwood <tcmreastw...@gmail.com>
Date:   Wed Feb 11 14:56:16 2015 +0000

    uniq: add support for writing output files

diff --git a/uniq.1 b/uniq.1
index 08d190b..762601e 100644
--- a/uniq.1
+++ b/uniq.1
@@ -10,7 +10,7 @@
 .Op Fl d | u
 .Op Fl f Ar fields
 .Op Fl s Ar chars
-.Op Ar file
+.Op Ar input Op Ar output
 .Sh DESCRIPTION
 .Nm
 reads
diff --git a/uniq.c b/uniq.c
index c01a758..1e7d09c 100644
--- a/uniq.c
+++ b/uniq.c
@@ -8,9 +8,9 @@
 #include "text.h"
 #include "util.h"
 
-static void uniqline(char *);
-static void uniq(FILE *, const char *);
-static void uniqfinish(void);
+static void uniqline(FILE *, char *);
+static void uniq(FILE *, FILE *);
+static void uniqfinish(FILE *);
 
 static const char *countfmt = "";
 static int dflag = 0;
@@ -25,13 +25,14 @@ static long prevlinecount = 0;
 static void
 usage(void)
 {
-       eprintf("usage: %s [-c] [-d | -u] [-f fields] [-s chars] [file]\n", 
argv0);
+       eprintf("usage: %s [-c] [-d | -u] [-f fields] [-s chars]"
+               " [[input] output]\n", argv0);
 }
 
 int
 main(int argc, char *argv[])
 {
-       FILE *fp;
+       FILE *fp = stdin, *ofp = stdout;
 
        ARGBEGIN {
        case 'c':
@@ -54,15 +55,24 @@ main(int argc, char *argv[])
        } ARGEND;
 
        if (argc == 0) {
-               uniq(stdin, "<stdin>");
-       } else if (argc == 1) {
-               if (!(fp = fopen(argv[0], "r")))
+               uniq(stdin, stdout);
+       } else if (argc >= 1) {
+               if (strcmp(argv[0], "-") && !(fp = fopen(argv[0], "r")))
                        eprintf("fopen %s:", argv[0]);
-               uniq(fp, argv[0]);
-               fclose(fp);
+               if (argc == 2) {
+                       if (strcmp(argv[1], "-") &&
+                           !(ofp = fopen(argv[1], "w")))
+                               eprintf("fopen %s:", argv[1]);
+               } else
+                       eprintf("extra argument: %s\n", argv[2]);
+               uniq(fp, ofp);
+               if (fp != stdin)
+                       fclose(fp);
        } else
                usage();
-       uniqfinish();
+       uniqfinish(ofp);
+       if (ofp != stdout)
+               fclose(ofp);
 
        return 0;
 }
@@ -84,7 +94,7 @@ uniqskip(char *l)
 }
 
 static void
-uniqline(char *l)
+uniqline(FILE *ofp, char *l)
 {
        char *loffset = l ? uniqskip(l) : l;
 
@@ -100,8 +110,8 @@ uniqline(char *l)
        if (prevline) {
                if ((prevlinecount == 1 && !dflag) ||
                    (prevlinecount != 1 && !uflag)) {
-                       printf(countfmt, prevlinecount);
-                       fputs(prevline, stdout);
+                       fprintf(ofp, countfmt, prevlinecount);
+                       fputs(prevline, ofp);
                }
                free(prevline);
                prevline = prevoffset = NULL;
@@ -115,17 +125,17 @@ uniqline(char *l)
 }
 
 static void
-uniq(FILE *fp, const char *str)
+uniq(FILE *fp, FILE *ofp)
 {
        char *buf = NULL;
        size_t size = 0;
 
        while (getline(&buf, &size, fp) != -1)
-               uniqline(buf);
+               uniqline(ofp, buf);
 }
 
 static void
-uniqfinish(void)
+uniqfinish(FILE *ofp)
 {
-       uniqline(NULL);
+       uniqline(ofp, NULL);
 }