X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=inline;f=src%2Flibpspp%2Fstr.c;h=86e7fd9199a5b9e22fba9fa2ac2eec4e9e7ff1c7;hb=e609c7d767ffd600fd844327b292590259cbb0de;hp=a58473192e44c1f7dc3cc59c2ac7b3e0deed373a;hpb=8c76dd167f2b63b3c97606c53667c391c17fae10;p=pspp

diff --git a/src/libpspp/str.c b/src/libpspp/str.c
index a58473192e..86e7fd9199 100644
--- a/src/libpspp/str.c
+++ b/src/libpspp/str.c
@@ -301,6 +301,39 @@ overflow:
   return false;
 }
 
+/* Copies IN to buffer OUT with size OUT_SIZE, appending a null terminator.  If
+   IN is too long for OUT, or if IN contains a new-line, replaces the tail with
+   "...".
+
+   OUT_SIZE must be at least 16. */
+void
+str_ellipsize (struct substring in, char *out, size_t out_size)
+{
+  assert (out_size >= 16);
+
+  size_t out_maxlen = out_size - 1;
+  if (in.length > out_maxlen - 3)
+    out_maxlen -= 3;
+
+  size_t out_len = 0;
+  while (out_len < in.length
+         && in.string[out_len] != '\n'
+         && in.string[out_len] != '\0'
+         && (in.string[out_len] != '\r'
+             || out_len + 1 >= in.length
+             || in.string[out_len + 1] != '\n'))
+    {
+      int mblen = u8_mblen (CHAR_CAST (const uint8_t *, in.string + out_len),
+                            in.length - out_len);
+      if (mblen < 0 || out_len + mblen > out_maxlen)
+        break;
+      out_len += mblen;
+    }
+
+  memcpy (out, in.string, out_len);
+  strcpy (&out[out_len], out_len < in.length ? "..." : "");
+}
+
 /* Sets the SIZE bytes starting at BLOCK to C,
    and returns the byte following BLOCK. */
 void *
@@ -392,6 +425,15 @@ ss_dealloc (struct substring *ss)
   free (ss->string);
 }
 
+/* Exchanges the contents of A and B. */
+void
+ss_swap (struct substring *a, struct substring *b)
+{
+  struct substring tmp = *a;
+  *a = *b;
+  *b = tmp;
+}
+
 /* Truncates SS to at most CNT bytes in length. */
 void
 ss_truncate (struct substring *ss, size_t cnt)
@@ -1481,7 +1523,8 @@ ds_put_cstr (struct string *st, const char *s)
 void
 ds_put_substring (struct string *st, struct substring ss)
 {
-  memcpy (ds_put_uninit (st, ss_length (ss)), ss_data (ss), ss_length (ss));
+  if (ss.length)
+    memcpy (ds_put_uninit (st, ss_length (ss)), ss_data (ss), ss_length (ss));
 }
 
 /* Returns ds_end(ST) and THEN increases the length by INCR. */