ash: deal with some TODOs (mostly trivial)

[oweals/busybox.git] / libbb / get_line_from_file.c

diff --git a/libbb/get_line_from_file.c b/libbb/get_line_from_file.c
index 56761f941959112a02b21547f9e76f768e6a9229..3cb46d240fb9d2bb95aa41e532f01b9fb636b99f 100644 (file)
--- a/libbb/get_line_from_file.c
+++ b/libbb/get_line_from_file.c
@@ -9,14 +9,22 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
+/* for getline() [GNUism]
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+*/
 #include "libbb.h"
 
 /* This function reads an entire line from a text file, up to a newline
  * or NUL byte, inclusive.  It returns a malloc'ed char * which
  * must be free'ed by the caller.  If end is NULL '\n' isn't considered
- * end of line.  If end isn't NULL, length of the chunk read is stored in it.
- * Return NULL if EOF/error */
-char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
+ * end of line.  If end isn't NULL, length of the chunk is stored in it.
+ * If lineno is not NULL, *lineno is incremented for each line,
+ * and also trailing '\' is recognized as line continuation.
+ *
+ * Returns NULL if EOF/error. */
+char* FAST_FUNC bb_get_chunk_with_continuation(FILE *file, int *end, int *lineno)
 {
        int ch;
        int idx = 0;
@@ -26,12 +34,20 @@ char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
        while ((ch = getc(file)) != EOF) {
                /* grow the line buffer as necessary */
                if (idx >= linebufsz) {
-                       linebufsz += 80;
+                       linebufsz += 256;
                        linebuf = xrealloc(linebuf, linebufsz);
                }
                linebuf[idx++] = (char) ch;
-               if (!ch || (end && ch == '\n'))
+               if (!ch)
                        break;
+               if (end && ch == '\n') {
+                       if (lineno == NULL)
+                               break;
+                       (*lineno)++;
+                       if (idx < 2 || linebuf[idx-2] != '\\')
+                               break;
+                       idx -= 2;
+               }
        }
        if (end)
                *end = idx;
@@ -48,6 +64,11 @@ char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
        return linebuf;
 }
 
+char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
+{
+       return bb_get_chunk_with_continuation(file, end, NULL);
+}
+
 /* Get line, including trailing \n if any */
 char* FAST_FUNC xmalloc_fgets(FILE *file)
 {
@@ -55,7 +76,6 @@ char* FAST_FUNC xmalloc_fgets(FILE *file)
 
        return bb_get_chunk_from_file(file, &i);
 }
-
 /* Get line.  Remove trailing \n */
 char* FAST_FUNC xmalloc_fgetline(FILE *file)
 {
@@ -68,6 +88,43 @@ char* FAST_FUNC xmalloc_fgetline(FILE *file)
        return c;
 }
 
+#if 0
+/* GNUism getline() should be faster (not tested) than a loop with fgetc */
+
+/* Get line, including trailing \n if any */
+char* FAST_FUNC xmalloc_fgets(FILE *file)
+{
+       char *res_buf = NULL;
+       size_t res_sz;
+
+       if (getline(&res_buf, &res_sz, file) == -1) {
+               free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */
+               res_buf = NULL;
+       }
+//TODO: trimming to res_sz?
+       return res_buf;
+}
+/* Get line.  Remove trailing \n */
+char* FAST_FUNC xmalloc_fgetline(FILE *file)
+{
+       char *res_buf = NULL;
+       size_t res_sz;
+
+       res_sz = getline(&res_buf, &res_sz, file);
+
+       if ((ssize_t)res_sz != -1) {
+               if (res_buf[res_sz - 1] == '\n')
+                       res_buf[--res_sz] = '\0';
+//TODO: trimming to res_sz?
+       } else {
+               free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */
+               res_buf = NULL;
+       }
+       return res_buf;
+}
+
+#endif
+
 #if 0
 /* Faster routines (~twice as fast). +170 bytes. Unused as of 2008-07.
  *