From e9519e44a65fa80fa473cfd2041af4e7f428b81a Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 16 Dec 2018 17:06:07 +0100 Subject: bc: fix handling of 'return' not in functions, and 'define f(){...}' function old new delta zbc_vm_process 561 597 +36 zbc_parse_stmt_possibly_auto 2232 2253 +21 zbc_lex_number 192 200 +8 zbc_num_divmod 150 156 +6 bc_vm_run 134 139 +5 bc_vm_init 757 760 +3 bc_num_printNewline 51 54 +3 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 7/0 up/down: 82/0) Total: 82 bytes text data bss dec hex filename 982138 485 7296 989919 f1adf busybox_old 982247 485 7296 990028 f1b4c busybox_unstripped Signed-off-by: Denys Vlasenko --- miscutils/bc.c | 32 ++++++++++++++++++++++++-------- testsuite/bc.tests | 5 +++++ 2 files changed, 29 insertions(+), 8 deletions(-) diff --git a/miscutils/bc.c b/miscutils/bc.c index 95ba8b094..4dc382476 100644 --- a/miscutils/bc.c +++ b/miscutils/bc.c @@ -591,6 +591,8 @@ typedef struct BcParse { //TODO: needed? Example? size_t nbraces; + + size_t in_funcdef; } BcParse; typedef struct BcProgram { @@ -4057,19 +4059,16 @@ static BC_STATUS zbc_parse_return(BcParse *p) { BcStatus s; BcLexType t; - bool paren; dbg_lex_enter("%s:%d entered", __func__, __LINE__); - s = zbc_lex_next(&p->l); if (s) RETURN_STATUS(s); t = p->l.t.t; - paren = t == BC_LEX_LPAREN; - if (t == BC_LEX_NLINE || t == BC_LEX_SCOLON) bc_parse_push(p, BC_INST_RET0); else { + bool paren = (t == BC_LEX_LPAREN); s = bc_parse_expr_empty_ok(p, 0, bc_parse_next_expr); if (s == BC_STATUS_PARSE_EMPTY_EXP) { bc_parse_push(p, BC_INST_RET0); @@ -4390,7 +4389,7 @@ static BC_STATUS zbc_parse_break_or_continue(BcParse *p, BcLexType type) # define zbc_parse_break_or_continue(...) (zbc_parse_break_or_continue(__VA_ARGS__), BC_STATUS_SUCCESS) #endif -static BC_STATUS zbc_parse_func(BcParse *p) +static BC_STATUS zbc_parse_funcdef(BcParse *p) { BcStatus s; bool var, comma = false; @@ -4454,7 +4453,16 @@ static BC_STATUS zbc_parse_func(BcParse *p) if (p->l.t.t != BC_LEX_LBRACE) s = bc_POSIX_requires("the left brace be on the same line as the function header"); + // Prevent "define z()" to be interpreted as function with empty stmt as body + while (p->l.t.t == BC_LEX_NLINE) { + s = zbc_lex_next(&p->l); + if (s) RETURN_STATUS(s); + } +//TODO: GNU bc requires a {} block even if function body has single stmt, enforce this? + + p->in_funcdef++; // to determine whether "return" stmt is allowed, and such s = zbc_parse_stmt_possibly_auto(p, true); + p->in_funcdef--; if (s) RETURN_STATUS(s); bc_parse_push(p, BC_INST_RET0); @@ -4467,7 +4475,7 @@ err: RETURN_STATUS(s); } #if ERRORS_ARE_FATAL -# define zbc_parse_func(...) (zbc_parse_func(__VA_ARGS__), BC_STATUS_SUCCESS) +# define zbc_parse_funcdef(...) (zbc_parse_funcdef(__VA_ARGS__), BC_STATUS_SUCCESS) #endif static BC_STATUS zbc_parse_auto(BcParse *p) @@ -4626,6 +4634,8 @@ static BC_STATUS zbc_parse_stmt_possibly_auto(BcParse *p, bool auto_allowed) // not when it is executed QUIT_OR_RETURN_TO_MAIN; case BC_LEX_KEY_RETURN: + if (!p->in_funcdef) + RETURN_STATUS(bc_error("'return' not in a function")); s = zbc_parse_return(p); break; case BC_LEX_KEY_WHILE: @@ -4657,7 +4667,7 @@ static BC_STATUS zbc_parse_stmt_or_funcdef(BcParse *p) s = bc_error("end of file"); else if (p->l.t.t == BC_LEX_KEY_DEFINE) { dbg_lex("%s:%d p->l.t.t:BC_LEX_KEY_DEFINE", __func__, __LINE__); - s = zbc_parse_func(p); + s = zbc_parse_funcdef(p); } else { dbg_lex("%s:%d p->l.t.t:%d (not BC_LEX_KEY_DEFINE)", __func__, __LINE__, p->l.t.t); s = zbc_parse_stmt(p); @@ -7021,7 +7031,13 @@ static BC_STATUS zbc_vm_stdin(void) bc_lex_file(&G.prs.l); G.use_stdin = 1; - s = zbc_vm_process(""); + do { + s = zbc_vm_process(""); + // We do not stop looping on errors here. + // Example: start interactive bc and enter "return". + // It should say "'return' not in a function" + // but should not exit. + } while (G.use_stdin); RETURN_STATUS(s); } #if ERRORS_ARE_FATAL diff --git a/testsuite/bc.tests b/testsuite/bc.tests index 86220ad19..093b3950e 100755 --- a/testsuite/bc.tests +++ b/testsuite/bc.tests @@ -51,6 +51,11 @@ testing "bc define auto" \ "8\n9\n" \ "" "define w() { auto z; return 8; }; w(); 9" +testing "bc define with body on next line" \ + "bc" \ + "8\n9\n" \ + "" "define w()\n{ auto z; return 8; }\nw()\n9" + tar xJf bc_large.tar.xz for f in bc*.bc; do -- cgit v1.2.3