1 files changed, 123 insertions, 0 deletions
diff --git a/src/skaembutils/s6-sort.c b/src/skaembutils/s6-sort.c
new file mode 100644
index 0000000..5b259b8
--- /dev/null
+++ b/src/skaembutils/s6-sort.c
@@ -0,0 +1,123 @@
+/* ISC license. */
+
+#include <stdlib.h>
+#include <errno.h>
+#include <skalibs/allreadwrite.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/buffer.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/skamisc.h>
+
+#define USAGE "s6-sort [ -bcfru0 ]"
+
+typedef int strncmp_t (char const *, unsigned int, char const *) ;
+typedef strncmp_t *strncmp_t_ref ;
+typedef int qsortcmp_t (void const *, void const *) ;
+typedef qsortcmp_t *qsortcmp_t_ref ;
+
+static int flagnoblanks = 0, flagreverse = 0, flaguniq = 0 ;
+
+static int str_diffb_f (register char const *s1, register unsigned int n, register char const *s2)
+{
+  return str_diffb(s1, n, s2) ;
+}
+
+static strncmp_t_ref comp = &str_diffb_f ;
+
+static int compit (register char const *s1, register unsigned int n1, register char const *s2, register unsigned int n2)
+{
+  register int r ;
+  if (flagnoblanks)
+  {
+    while ((*s1 == ' ') || (*s1 == '\t')) (s1++, n1--) ;
+    while ((*s2 == ' ') || (*s2 == '\t')) (s2++, n2--) ;
+  }
+  r = (*comp)(s1, n1 < n2 ? n1 : n2, s2) ;
+  if (!r) r = n1 - n2 ;
+  return flagreverse ? -r : r ;
+}
+
+static int sacmp (stralloc const *a, stralloc const *b)
+{
+  return compit(a->s, a->len - 1, b->s, b->len - 1) ;
+}
+
+static int slurplines (genalloc *lines, char sep)
+{
+  unsigned int i = 0 ;
+  for (;; i++)
+  {
+    stralloc sa = STRALLOC_ZERO ;
+    int r = skagetln(buffer_0, &sa, sep) ;
+    if (!r) break ;
+    if ((r < 0) && ((errno != EPIPE) || !stralloc_catb(&sa, &sep, 1)))
+      return -1 ;
+    stralloc_shrink(&sa) ;
+    if (!genalloc_append(stralloc, lines, &sa)) return -1 ;
+  }
+  return (int)i ;
+}
+
+static void uniq (genalloc *lines)
+{
+  unsigned int len = genalloc_len(stralloc, lines) ;
+  register stralloc *s = genalloc_s(stralloc, lines) ;
+  register unsigned int i = 1 ;
+  for (; i < len ; i++)
+    if (!sacmp(s+i-1, s+i)) stralloc_free(s+i-1) ;
+}
+
+static int outputlines (stralloc const *s, unsigned int len)
+{
+  register unsigned int i = 0 ;
+  for (; i < len ; i++)
+    if (buffer_put(buffer_1, s[i].s, s[i].len) < 0) return 0 ;
+  return buffer_flush(buffer_1) ;
+}
+
+static int check (stralloc const *s, unsigned int len)
+{
+  register unsigned int i = 1 ;
+  for (; i < len ; i++)
+    if (sacmp(s+i-1, s+i) >= !flaguniq) return 0 ;
+  return 1 ;
+}
+
+int main (int argc, char const *const *argv)
+{
+  genalloc lines = GENALLOC_ZERO ; /* array of stralloc */
+  char sep = '\n' ;
+  int flagcheck = 0 ;
+  PROG = "s6-sort" ;
+  {
+    subgetopt_t l = SUBGETOPT_ZERO ;
+    for (;;)
+    {
+      register int opt = subgetopt_r(argc, argv, "bcfru0", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case 'b' : flagnoblanks = 1 ; break ;
+        case 'c' : flagcheck = 1 ; break ;
+        case 'f' : comp = &case_diffb ; break ;
+        case 'r' : flagreverse = 1 ; break ;
+        case 'u' : flaguniq = 1 ; break ;
+        case '0' : sep = '\0' ; break ;
+        default : strerr_dieusage(100, USAGE) ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+  }
+
+  if (slurplines(&lines, sep) < 0) strerr_diefu1sys(111, "read from stdin") ;
+  if (flagcheck) return !check(genalloc_s(stralloc, &lines), genalloc_len(stralloc, &lines)) ;
+  qsort(genalloc_s(stralloc, &lines), genalloc_len(stralloc, &lines), sizeof(stralloc), (qsortcmp_t_ref)&sacmp) ;
+  if (flaguniq) uniq(&lines) ;
+  if (!outputlines(genalloc_s(stralloc, &lines), genalloc_len(stralloc, &lines)))
+    strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}