libbb: introduce xmalloc_xopen_read_close and use where appropriate

instead of xmalloc_open_read_close.

function                                             old     new   delta
xmalloc_xopen_read_close                               -      34     +34
xmalloc_open_read_close                              163     171      +8
passwd_main                                         1070    1074      +4
rexecve                                              254     257      +3
handle_incoming_and_exit                            2657    2659      +2
parse_command                                       1509    1510      +1
buffer_fill_and_print                                 76      73      -3
evaltreenr                                           599     589     -10
evaltree                                             599     589     -10
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 5/3 up/down: 52/-23)             Total: 29 bytes

1 files changed, 5 insertions, 2 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 1c54a32d5..f9f28f983 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -556,7 +556,10 @@ extern char *reads(int fd, char *buf, size_t count);
 extern char *xmalloc_reads(int fd, char *pfx, size_t *maxsz_p);
 extern ssize_t read_close(int fd, void *buf, size_t maxsz);
 extern ssize_t open_read_close(const char *filename, void *buf, size_t maxsz);
+/* Returns NULL if file can't be opened */
 extern void *xmalloc_open_read_close(const char *filename, size_t *maxsz_p);
+/* Never returns NULL */
+extern void *xmalloc_xopen_read_close(const char *filename, size_t *maxsz_p);
 
 extern ssize_t safe_write(int fd, const void *buf, size_t count);
 // NB: will return short write on error, not -1,
@@ -568,9 +571,9 @@ extern void xwrite(int fd, const void *buf, size_t count);
 extern void xprint_and_close_file(FILE *file);
 /* Reads up to (and including) TERMINATING_STRING: */
 extern char *xmalloc_fgets_str(FILE *file, const char *terminating_string);
-/* Chops off TERMINATING_STRING: from the end: */
+/* Chops off TERMINATING_STRING from the end: */
 extern char *xmalloc_fgetline_str(FILE *file, const char *terminating_string);
-/* Reads up to (and including) "\n" or NUL byte */
+/* Reads up to (and including) "\n" or NUL byte: */
 extern char *xmalloc_fgets(FILE *file);
 /* Chops off '\n' from the end, unlike fgets: */
 extern char *xmalloc_fgetline(FILE *file);