hush: create a macro IS_NULL_WORD to test for null shell word

No logic changes

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

1 files changed, 14 insertions, 16 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 9ec813df2..10ade0b9e 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -558,6 +558,8 @@ typedef struct o_string {
         smallint has_empty_slot;
         smallint ended_in_ifs;
 } o_string;
+#define IS_NULL_WORD(str) \
+        ((str).length == 0 && !(str).has_quoted_part)
 enum {
         /* Protect all newly added chars against globbing by prepending \ to *, ?, [, -, \ */
         EXP_FLAG_GLOBPROTECT_CHARS = 0x1,
@@ -4271,7 +4273,7 @@ static int done_word(struct parse_context *ctx)
         struct command *command = ctx->command;
 
         debug_printf_parse("done_word entered: '%s' %p\n", ctx->word.data, command);
-        if (ctx->word.length == 0 && !ctx->word.has_quoted_part) {
+        if (IS_NULL_WORD(ctx->word)) {
                 debug_printf_parse("done_word return 0: no word, ignored\n");
                 return 0;
         }
@@ -4843,11 +4845,11 @@ static int parse_group(struct parse_context *ctx,
 
 #if 0 /* Prevented by caller */
         if (command->argv /* word [word]{... */
-         || ctx->word.length /* word{... */
-         || ctx->word.has_quoted_part /* ""{... */
-        )
+         || !IS_NULL_WORD(ctx->word) /* word{... or ""{... */
+        ) {
                 debug_printf_parse("parse_group return -1: "
                         "syntax error, groups and arglists don't mix\n");
+        }
 #endif
 
  IF_HUSH_FUNCTIONS(skip:)
@@ -5700,8 +5702,7 @@ static struct pipe *parse_stream(char **pstring,
 #endif
                 /* Are { and } special here? */
                 if (ctx.command->argv /* word [word]{... - non-special */
-                 || ctx.word.length       /* word{... - non-special */
-                 || ctx.word.has_quoted_part     /* ""{... - non-special */
+                 || !IS_NULL_WORD(ctx.word)  /* word{... ""{... - non-special */
                  || (next != ';'             /* }; - special */
                     && next != ')'           /* }) - special */
                     && next != '('           /* {( - special */
@@ -5756,8 +5757,7 @@ static struct pipe *parse_stream(char **pstring,
                                  * "case ... in <newline> word) ..."
                                  */
                                 if (IS_NULL_CMD(ctx.command)
-                                 && ctx.word.length == 0
-                                 && !ctx.word.has_quoted_part
+                                 && IS_NULL_WORD(ctx.word)
                                  && heredoc_cnt == 0
                                 ) {
                                         /* This newline can be ignored. But...
@@ -5805,9 +5805,8 @@ static struct pipe *parse_stream(char **pstring,
                  * Pathological example: { ""}; } should run "}" command.
                  */
                 if (ch == '}') {
-                        if (ctx.word.length != 0     /* word} */
-                         || ctx.word.has_quoted_part /* ""} */
-                        ) {
+                        if (!IS_NULL_WORD(ctx.word)) {
+                                /* word} or ""} */
                                 goto ordinary_char;
                         }
                         if (!IS_NULL_CMD(ctx.command)) { /* cmd } */
@@ -5928,7 +5927,7 @@ static struct pipe *parse_stream(char **pstring,
                                 goto parse_error_exitcode1;
                         continue; /* get next char */
                 case '#':
-                        if (ctx.word.length == 0 && !ctx.word.has_quoted_part) {
+                        if (IS_NULL_WORD(ctx.word)) {
                                 /* skip "#comment" */
                                 /* note: we do not add it to &ctx.as_string */
 /* TODO: in bash:
@@ -6086,8 +6085,8 @@ static struct pipe *parse_stream(char **pstring,
                                 }
                         } else {
                                 if (IS_NULL_CMD(ctx.command)) {
-                                        /* Example: "| cat" */
-                                        /* Example: "date | | cat" */
+                                        /* Testcase: sh -c '| cat' */
+                                        /* Testcase: sh -c 'date | | cat' */
                                         syntax_error_unexpected_ch('|');
                                         goto parse_error_exitcode1;
                                 }
@@ -6099,8 +6098,7 @@ static struct pipe *parse_stream(char **pstring,
                         /* "case... in [(]word)..." - skip '(' */
                         if (ctx.ctx_res_w == RES_MATCH
                          && ctx.command->argv == NULL /* not (word|(... */
-                         && ctx.word.length == 0 /* not word(... */
-                         && ctx.word.has_quoted_part == 0 /* not ""(... */
+                         && IS_NULL_WORD(ctx.word)    /* not word(... or ""(... */
                         ) {
                                 continue; /* get next char */
                         }