libbb: split bb_get_chunk_from_file and bb_get_chunk_with_continuation

This also moves bb_get_chunk_with_continuation into its sole user,
parse_config.c.
This allows to optimize both functions separately,
they need to be optimized for speed.
(this need was highlighted by slow modprobe caused in part by slow
bb_get_chunk_with_continuation in config parser).

function                                             old     new   delta
bb_get_chunk_from_file                                 7     130    +123
config_read                                          457     558    +101
bb_get_chunk_with_continuation                       194       -    -194
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 2/0 up/down: 224/-194)           Total: 30 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 2d46061da..5d2b4c8c1 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -730,8 +730,12 @@ extern void xclose(int fd) FAST_FUNC;
 /* Reads and prints to stdout till eof, then closes FILE. Exits on error: */
 extern void xprint_and_close_file(FILE *file) FAST_FUNC;
 
+/* Reads a line from a text file, up to a newline or NUL byte, inclusive.
+ * Returns malloc'ed char*. If end is NULL '\n' isn't considered
+ * end of line. If end isn't NULL, length of the chunk is stored in it.
+ * Returns NULL if EOF/error.
+ */
 extern char *bb_get_chunk_from_file(FILE *file, int *end) FAST_FUNC;
-extern char *bb_get_chunk_with_continuation(FILE *file, int *end, int *lineno) FAST_FUNC;
 /* Reads up to (and including) TERMINATING_STRING: */
 extern char *xmalloc_fgets_str(FILE *file, const char *terminating_string) FAST_FUNC RETURNS_MALLOC;
 /* Same, with limited max size, and returns the length (excluding NUL): */