diff options
Diffstat (limited to 'Src/lex.c')
| -rw-r--r-- | Src/lex.c | 55 |
1 files changed, 44 insertions, 11 deletions
diff --git a/Src/lex.c b/Src/lex.c index a334dc722..ddee689ae 100644 --- a/Src/lex.c +++ b/Src/lex.c @@ -548,6 +548,11 @@ add(int c) else\ parend = inbufct;} } +/* + * Return 1 for math, 0 for a command, 2 for an error. If it couldn't be + * parsed as math, but there was no gross error, it's a command. + */ + static int cmd_or_math(int cs_type) { @@ -558,14 +563,19 @@ cmd_or_math(int cs_type) c = dquote_parse(')', 0); cmdpop(); *bptr = '\0'; - if (c) - return 1; - c = hgetc(); - if (c == ')') - return 1; - hungetc(c); - lexstop = 0; - c = ')'; + if (!c) { + /* Successfully parsed, see if it was math */ + c = hgetc(); + if (c == ')') + return 1; /* yes */ + hungetc(c); + lexstop = 0; + c = ')'; + } else if (lexstop) { + /* we haven't got anything to unget */ + return 2; + } + /* else unsuccessful: unget the whole thing */ hungetc(c); lexstop = 0; while (len > oldlen) { @@ -576,18 +586,25 @@ cmd_or_math(int cs_type) return 0; } + +/* + * Parse either a $(( ... )) or a $(...) + * Return 0 on success, 1 on failure. + */ static int cmd_or_math_sub(void) { - int c = hgetc(); + int c = hgetc(), ret; if (c == '(') { add(Inpar); add('('); - if (cmd_or_math(CS_MATHSUBST)) { + if ((ret = cmd_or_math(CS_MATHSUBST)) == 1) { add(')'); return 0; } + if (ret == 2) + return 1; bptr -= 2; len -= 2; } else { @@ -781,7 +798,16 @@ gettok(void) if (incmdpos) { len = 0; bptr = tokstr = (char *) hcalloc(bsiz = 32); - return cmd_or_math(CS_MATH) ? DINPAR : INPAR; + switch (cmd_or_math(CS_MATH)) { + case 1: + return DINPAR; + + case 0: + return INPAR; + + default: + return LEXERR; + } } } else if (d == ')') return INOUTPAR; @@ -1328,6 +1354,9 @@ gettokstr(int c, int sub) return peek; } + +/* Return non-zero for error (character to unget), else zero */ + /**/ static int dquote_parse(char endchar, int sub) @@ -1466,6 +1495,10 @@ dquote_parse(char endchar, int sub) * to hungetc() a character on an error. However, I don't * understand what that actually gets us, and we can't guarantee * it's a character anyway, because of the previous test. + * + * We use the same feature in cmd_or_math we we actually do + * need to unget if we decide it's really a command substitution. + * We try to handle the other case by testing for lexstop. */ err = c; } |