[git commit] awk: enforce simple builtins' argument number

[Denys Vlasenko]

commit: https://git.busybox.net/busybox/commit/?id=47d9133896f0de6b17393309193051e4bd52015e
branch: https://git.busybox.net/busybox/commit/?id=refs/heads/master

function                                             old     new   delta
evaluate                                            3215    3303     +88
.rodata                                           104036  104107     +71
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 159/0)             Total: 159 bytes

Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 editors/awk.c | 45 ++++++++++++++++++++++++++++-----------------
 1 file changed, 28 insertions(+), 17 deletions(-)

diff --git a/editors/awk.c b/editors/awk.c
index fb841687e..1925e0771 100644
--- a/editors/awk.c
+++ b/editors/awk.c
@@ -464,11 +464,11 @@ static const uint32_t tokeninfo[] ALIGN4 = {
 // OC_B's are builtins with enforced minimum number of arguments (two upper bits).
 //  Highest byte bit pattern: nn s3s2s1 v3v2v1
 //  nn - min. number of args, sN - resolve Nth arg to string, vN - resolve to var
-// OC_FBLTIN's are builtins with one optional argument,
-//  TODO: enforce exactly one arg for: system, close, cos, sin, exp, int, log, sqrt
-//        zero args for: rand systime
-//  Do have one optional arg: fflush, srand, length
-#define OC_B  OC_BUILTIN
+// OC_FBLTIN's are builtins with zero or one argument.
+//  |Rx| enforces that arg is present for: system, close, cos, sin, exp, int, log, sqrt.
+//  Check for no args is present in builtins' code (not in this table): rand, systime.
+//  Have one _optional_ arg: fflush, srand, length
+#define OC_B   OC_BUILTIN
 #define A1     P(0x40) /*one arg*/
 #define A2     P(0x80) /*two args*/
 #define A3     P(0xc0) /*three args*/
@@ -480,15 +480,15 @@ static const uint32_t tokeninfo[] ALIGN4 = {
 #define _ss_vv P(0x1b)
 #define _s_vv_ P(0x16)
 #define ss_vv_ P(0x36)
-	OC_B|B_an|_vv|A2,    OC_B|B_co|__v|A1,    OC_B|B_ls|_vv|A2,  OC_B|B_or|_vv|A2,    // and    compl   lshift   or
-	OC_B|B_rs|_vv|A2,    OC_B|B_xo|_vv|A2,                                            // rshift xor
-	OC_FBLTIN|Sx|F_cl,   OC_FBLTIN|Sx|F_sy,   OC_FBLTIN|Sx|F_ff, OC_B|B_a2|_vv|A2,    // close  system  fflush   atan2
-	OC_FBLTIN|Nx|F_co,   OC_FBLTIN|Nx|F_ex,   OC_FBLTIN|Nx|F_in, OC_FBLTIN|Nx|F_lg,   // cos    exp     int      log
-	OC_FBLTIN|F_rn,      OC_FBLTIN|Nx|F_si,   OC_FBLTIN|Nx|F_sq, OC_FBLTIN|Nx|F_sr,   // rand   sin     sqrt     srand
-	OC_B|B_ge|_s_vv_|A3, OC_B|B_gs|ss_vv_|A2, OC_B|B_ix|_ss_vv|A2,                    // gensub gsub    index  /*length was here*/
-	OC_B|B_ma|__s__v|A2, OC_B|B_sp|__s_vv|A2, OC_SPRINTF,        OC_B|B_su|ss_vv_|A2, // match  split   sprintf  sub
-	OC_B|B_ss|__svvv|A2, OC_FBLTIN|F_ti,      OC_B|B_ti|__s_vv,  OC_B|B_mt|__s_vv,    // substr systime strftime mktime
-	OC_B|B_lo|__s__v|A1, OC_B|B_up|__s__v|A1,                                         // tolower toupper
+	OC_B|B_an|_vv|A2,    OC_B|B_co|__v|A1,    OC_B|B_ls|_vv|A2,    OC_B|B_or|_vv|A2,    // and    compl   lshift   or
+	OC_B|B_rs|_vv|A2,    OC_B|B_xo|_vv|A2,                                              // rshift xor
+	OC_FBLTIN|Sx|Rx|F_cl,OC_FBLTIN|Sx|Rx|F_sy,OC_FBLTIN|Sx|F_ff,   OC_B|B_a2|_vv|A2,    // close  system  fflush   atan2
+	OC_FBLTIN|Nx|Rx|F_co,OC_FBLTIN|Nx|Rx|F_ex,OC_FBLTIN|Nx|Rx|F_in,OC_FBLTIN|Nx|Rx|F_lg,// cos    exp     int      log
+	OC_FBLTIN|F_rn,      OC_FBLTIN|Nx|Rx|F_si,OC_FBLTIN|Nx|Rx|F_sq,OC_FBLTIN|Nx|F_sr,   // rand   sin     sqrt     srand
+	OC_B|B_ge|_s_vv_|A3, OC_B|B_gs|ss_vv_|A2, OC_B|B_ix|_ss_vv|A2,                      // gensub gsub    index  /*length was here*/
+	OC_B|B_ma|__s__v|A2, OC_B|B_sp|__s_vv|A2, OC_SPRINTF,          OC_B|B_su|ss_vv_|A2, // match  split   sprintf  sub
+	OC_B|B_ss|__svvv|A2, OC_FBLTIN|F_ti,      OC_B|B_ti|__s_vv,    OC_B|B_mt|__s_vv,    // substr systime strftime mktime
+	OC_B|B_lo|__s__v|A1, OC_B|B_up|__s__v|A1,                                           // tolower toupper
 	OC_FBLTIN|Sx|F_le,   // length
 	OC_GETLINE|SV,       // getline
 	0, 0, // func function
@@ -2773,8 +2773,11 @@ static var *evaluate(node *op, var *res)
 		debug_printf_eval("opinfo:%08x opn:%08x\n", opinfo, opn);
 
 		/* execute inevitable things */
-		if (opinfo & OF_RES1)
+		if (opinfo & OF_RES1) {
+			if ((opinfo & OF_REQUIRED) && !op1)
+				syntax_error(EMSG_TOO_FEW_ARGS);
 			L.v = evaluate(op1, TMPVAR0);
+		}
 		if (opinfo & OF_STR1) {
 			L.s = getvar_s(L.v);
 			debug_printf_eval("L.s:'%s'\n", L.s);
@@ -3101,12 +3104,18 @@ static var *evaluate(node *op, var *res)
 			double R_d = R_d; /* for compiler */
 			debug_printf_eval("FBLTIN\n");
 
+			if (op1 && (op1->info & OPCLSMASK) == OC_COMMA)
+				/* Simple builtins take one arg maximum */
+				syntax_error("Too many arguments");
+
 			switch (opn) {
 			case F_in:
 				R_d = (long long)L_d;
 				break;
 
-			case F_rn:
+			case F_rn: /*rand*/
+				if (op1)
+					syntax_error("Too many arguments");
 				R_d = (double)rand() / (double)RAND_MAX;
 				break;
 
@@ -3149,7 +3158,9 @@ static var *evaluate(node *op, var *res)
 				srand(seed);
 				break;
 
-			case F_ti:
+			case F_ti: /*systime*/
+				if (op1)
+					syntax_error("Too many arguments");
 				R_d = time(NULL);
 				break;