[hackers] [sbase] sort: Implement -c and -C flags || Michael Forney

From: <git_AT_suckless.org>
Date: Sun, 23 Nov 2014 20:42:18 +0100

commit cb427d553af31c30c1c1ca0c1490374fee1b6cdb
Author: Michael Forney <mforney_AT_mforney.org>
Date: Sun Nov 23 19:35:56 2014 +0000

    sort: Implement -c and -C flags

diff --git a/sort.1 b/sort.1
index 12fb95d..71c8154 100644
--- a/sort.1
+++ b/sort.1
_AT_@ -15,9 +15,20 @@ writes the sorted concatenation of the given files to stdout. If no file is
 given, sort reads from stdin.
 .SH OPTIONS
 .TP
+.B \-C
+check that the concatenation of the given files is sorted rather than sorting
+them. In this mode, no output is printed to stdout, and the exit status
+indicates the result of the check.
+.TP
 .B \-b
 skip leading whitespace of columns when sorting.
 .TP
+.B \-c
+the same as
+.B \-C
+except that when disorder is detected, a message is printed to stderr
+indicating the location of the disorder.
+.TP
 .BI \-k \ key
 specifies a key definition of the form
 .BR S [. s ][ f ][, E [. e ][ f ]]
diff --git a/sort.c b/sort.c
index 2a89870..c4cd81f 100644
--- a/sort.c
+++ b/sort.c
_AT_@ -32,6 +32,7 @@ static struct kdlist *head = NULL;
 static struct kdlist *tail = NULL;
 
 static void addkeydef(char *, int);
+static void check(FILE *);
 static void freelist(void);
 static int linecmp(const char **, const char **);
 static char *skipblank(char *);
_AT_@ -40,13 +41,13 @@ static int parse_keydef(struct keydef *, char *, int);
 static char *nextcol(char *);
 static char *columns(char *, const struct keydef *);
 
-static int uflag = 0;
+static int Cflag = 0, cflag = 0, uflag = 0;
 static char *fieldsep = NULL;
 
 static void
 usage(void)
 {
- enprintf(2, "usage: %s [-bnru] [-t delim] [-k def]... [file...]\n", argv0);
+ enprintf(2, "usage: %s [-Cbcnru] [-t delim] [-k def]... [file...]\n", argv0);
 }
 
 int
_AT_@ -58,9 +59,15 @@ main(int argc, char *argv[])
         int global_flags = 0;
 
         ARGBEGIN {
+ case 'C':
+ Cflag = 1;
+ break;
         case 'b':
                 global_flags |= MOD_STARTB | MOD_ENDB;
                 break;
+ case 'c':
+ cflag = 1;
+ break;
         case 'k':
                 addkeydef(EARGF(usage()), global_flags);
                 break;
_AT_@ -87,22 +94,33 @@ main(int argc, char *argv[])
         addkeydef("1", global_flags & MOD_R);
 
         if (argc == 0) {
- getlines(stdin, &linebuf);
+ if (Cflag || cflag) {
+ check(stdin);
+ } else {
+ getlines(stdin, &linebuf);
+ }
         } else for (; argc > 0; argc--, argv++) {
                 if (!(fp = fopen(argv[0], "r"))) {
                         enprintf(2, "fopen %s:", argv[0]);
                         continue;
                 }
- getlines(fp, &linebuf);
+ if (Cflag || cflag) {
+ check(fp);
+ } else {
+ getlines(fp, &linebuf);
+ }
                 fclose(fp);
         }
- qsort(linebuf.lines, linebuf.nlines, sizeof *linebuf.lines,
- (int (*)(const void *, const void *))linecmp);
 
- for (i = 0; i < linebuf.nlines; i++) {
- if (!uflag || i == 0 || linecmp((const char **)&linebuf.lines[i],
- (const char **)&linebuf.lines[i-1])) {
- fputs(linebuf.lines[i], stdout);
+ if (!Cflag && !cflag) {
+ qsort(linebuf.lines, linebuf.nlines, sizeof *linebuf.lines,
+ (int (*)(const void *, const void *))linecmp);
+
+ for (i = 0; i < linebuf.nlines; i++) {
+ if (!uflag || i == 0 || linecmp((const char **)&linebuf.lines[i],
+ (const char **)&linebuf.lines[i-1])) {
+ fputs(linebuf.lines[i], stdout);
+ }
                 }
         }
 
_AT_@ -129,6 +147,25 @@ addkeydef(char *def, int flags)
 }
 
 static void
+check(FILE *fp)
+{
+ static struct { char *buf; size_t size; } prev, cur, tmp;
+
+ if (!prev.buf)
+ getline(&prev.buf, &prev.size, fp);
+ while (getline(&cur.buf, &cur.size, fp) != -1) {
+ if (uflag > linecmp((const char **) &cur.buf, (const char **) &prev.buf)) {
+ if (!Cflag)
+ weprintf("disorder: %s", cur.buf);
+ exit(1);
+ }
+ tmp = cur;
+ cur = prev;
+ prev = tmp;
+ }
+}
+
+static void
 freelist(void)
 {
         struct kdlist *node;
Received on Sun Nov 23 2014 - 20:42:18 CET