Do not treat isolated CR in input data as new-line.

[pspp-builds.git] / src / libpspp / str.c

diff --git a/src/libpspp/str.c b/src/libpspp/str.c
index 44d325e072df297eb80977d1f03abd45af6bd543..71f54474d57f995f8c5b73572e1d8f761b7e934e 100644 (file)
--- a/src/libpspp/str.c
+++ b/src/libpspp/str.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 1997-9, 2000, 2006, 2009 Free Software Foundation, Inc.
+   Copyright (C) 1997-9, 2000, 2006, 2009, 2010 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -23,6 +23,7 @@
 #include <stdint.h>
 #include <stdlib.h>
 
+#include <libpspp/cast.h>
 #include <libpspp/message.h>
 #include <libpspp/pool.h>
 
@@ -1071,6 +1072,34 @@ ds_set_length (struct string *st, size_t new_length, char pad)
     st->ss.length = new_length;
 }
 
+/* Removes N characters from ST starting at offset START. */
+void
+ds_remove (struct string *st, size_t start, size_t n)
+{
+  if (n > 0 && start < st->ss.length)
+    {
+      if (st->ss.length - start <= n)
+        {
+          /* All characters at or beyond START are deleted. */
+          st->ss.length = start;
+        }
+      else
+        {
+          /* Some characters remain and must be shifted into
+             position. */
+          memmove (st->ss.string + st->ss.length,
+                   st->ss.string + st->ss.length + n,
+                   st->ss.length - start - n);
+          st->ss.length -= n;
+        }
+    }
+  else
+    {
+      /* There are no characters to delete or no characters at or
+         beyond START, hence deletion is a no-op. */
+    }
+}
+
 /* Returns true if ST is empty, false otherwise. */
 bool
 ds_is_empty (const struct string *st)
@@ -1186,13 +1215,24 @@ ds_capacity (const struct string *st)
 char *
 ds_cstr (const struct string *st_)
 {
-  struct string *st = (struct string *) st_;
+  struct string *st = CONST_CAST (struct string *, st_);
   if (st->ss.string == NULL)
     ds_extend (st, 1);
   st->ss.string[st->ss.length] = '\0';
   return st->ss.string;
 }
 
+/* Returns the value of ST as a null-terminated string and then
+   reinitialized ST as an empty string.  The caller must free the
+   returned string with free(). */
+char *
+ds_steal_cstr (struct string *st)
+{
+  char *s = ds_cstr (st);
+  ds_init_empty (st);
+  return s;
+}
+
 /* Reads characters from STREAM and appends them to ST, stopping
    after MAX_LENGTH characters, after appending a newline, or
    after an I/O error or end of file was encountered, whichever
@@ -1200,9 +1240,9 @@ ds_cstr (const struct string *st_)
    to ST, false if no characters were read before an I/O error or
    end of file (or if MAX_LENGTH was 0).
 
-   This function accepts LF, CR LF, and CR sequences as new-line,
-   and translates each of them to a single '\n' new-line
-   character in ST. */
+   This function treats LF and CR LF sequences as new-line,
+   translating each of them to a single '\n' new-line character
+   in ST. */
 bool
 ds_read_line (struct string *st, FILE *stream, size_t max_length)
 {
@@ -1211,21 +1251,36 @@ ds_read_line (struct string *st, FILE *stream, size_t max_length)
   for (length = 0; length < max_length; length++)
     {
       int c = getc (stream);
-      if (c == EOF)
-        break;
-
-      if (c == '\r')
+      switch (c)
         {
+        case EOF:
+          return length > 0;
+
+        case '\n':
+          ds_put_char (st, c);
+          return true;
+
+        case '\r':
           c = getc (stream);
-          if (c != '\n')
+          if (c == '\n')
+            {
+              /* CR followed by LF is special: translate to \n. */
+              ds_put_char (st, '\n');
+              return true;
+            }
+          else
             {
+              /* CR followed by anything else is just CR. */
+              ds_put_char (st, '\r');
+              if (c == EOF)
+                return true;
               ungetc (c, stream);
-              c = '\n';
             }
+          break;
+
+        default:
+          ds_put_char (st, c);
         }
-      ds_put_char (st, c);
-      if (c == '\n')
-        return true;
     }
 
   return length > 0;
@@ -1413,3 +1468,25 @@ ds_relocate (struct string *st)
       free ((char *) rel);
     }
 }
+
+
+\f
+
+/* Operations on uint8_t "strings" */
+
+/* Copies buffer SRC, of SRC_SIZE bytes, to DST, of DST_SIZE bytes.
+   DST is truncated to DST_SIZE bytes or padded on the right with
+   copies of PAD as needed. */
+void
+u8_buf_copy_rpad (uint8_t *dst, size_t dst_size,
+                 const uint8_t *src, size_t src_size,
+                 char pad)
+{
+  if (src_size >= dst_size)
+    memmove (dst, src, dst_size);
+  else
+    {
+      memmove (dst, src, src_size);
+      memset (&dst[src_size], pad, dst_size - src_size);
+    }
+}