Add support for .WARNINGS special variable

Create a new special variable, .WARNINGS, to allow per-makefile
control over warnings.  The command line settings will override
this.

Move the handling of warning flags to a new file: src/warning.c.
Allow the decode to work with generic strings, and call it from
decode_switches().

* Makefile.am: Add new file src/warning.c.
* build_w32.bat: Ditto.
* builddos.bat: Ditto.
* po/POTFILES.in: Ditto.
* src/makeint.h: #define for the .WARNINGS variable name.
* src/warning.h: Add declarations for methods moved from main.c.
Rename the enum warning_state to warning_action.
* src/warning.c: New file.  Move all warning encode/decode here
from main.c.
* src/main.c: Move methods into warning.c and call those methods
instead.
(main): Set .WARNINGS as a special variable.
* src/job.c (construct_command_argv): Rename to warning_action.
* src/read.c (tilde_expand): Ditto.
* src/variable.c (set_special_var): Update warnings when the
.WARNINGS special variable is set.
* tests/scripts/options/warn: Check invalid warning options.
* tests/scripts/variables/WARNINGS: Add tests for the .WARNINGS
special variable.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/misc.c b/src/misc.c
index 80fd63ac..04437c2b 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -437,6 +437,7 @@ find_next_token (const char **ptr, size_t *lengthptr)
   return (char *)p;
 }
 
+
 /* Write a BUFFER of size LEN to file descriptor FD.
    Retry short writes from EINTR.  Return LEN, or -1 on error.  */
 ssize_t
@@ -611,7 +612,7 @@ get_tmpdir ()
       unsigned int found = 0;
 
       for (tp = tlist; *tp; ++tp)
-        if ((tmpdir = getenv (*tp)) && *tmpdir != '\0')
+        if ((tmpdir = getenv (*tp)) != NULL && *tmpdir != '\0')
           {
             struct stat st;
             int r;