This patch extends pgbench expression with functions. Currently only one
"abs" function is added. The point is rather to bootstrap the
infrastructure for other functions (such as hash, random variants...) to
be added later.
--
Fabien.
diff --git a/contrib/pgbench/exprparse.y b/contrib/pgbench/exprparse.y
index 243c6b9..fd396bd 100644
--- a/contrib/pgbench/exprparse.y
+++ b/contrib/pgbench/exprparse.y
@@ -20,6 +20,7 @@ static PgBenchExpr *make_integer_constant(int64 ival);
static PgBenchExpr *make_variable(char *varname);
static PgBenchExpr *make_op(char operator, PgBenchExpr *lexpr,
PgBenchExpr *rexpr);
+static PgBenchExpr *make_func(const char *fname, PgBenchExpr *arg1);
%}
@@ -35,8 +36,8 @@ static PgBenchExpr *make_op(char operator, PgBenchExpr *lexpr,
%type <expr> expr
%type <ival> INTEGER
-%type <str> VARIABLE
-%token INTEGER VARIABLE
+%type <str> VARIABLE FUNCTION
+%token INTEGER VARIABLE FUNCTION
%token CHAR_ERROR /* never used, will raise a syntax error */
%left '+' '-'
@@ -57,6 +58,7 @@ expr: '(' expr ')' { $$ = $2; }
| expr '%' expr { $$ = make_op('%', $1, $3); }
| INTEGER { $$ = make_integer_constant($1); }
| VARIABLE { $$ = make_variable($1); }
+ | FUNCTION '(' expr ')' { $$ = make_func($1, $3); pg_free($1); }
;
%%
@@ -93,4 +95,32 @@ make_op(char operator, PgBenchExpr *lexpr, PgBenchExpr *rexpr)
return expr;
}
+static struct {
+ char * fname;
+ int nargs;
+ PgBenchFunction tag;
+} PGBENCH_FUNCTIONS[] = {
+ { "abs", 1, PGBENCH_ABS }
+};
+
+static PgBenchExpr *
+make_func(const char * fname, PgBenchExpr *arg1)
+{
+ PgBenchExpr *expr = pg_malloc(sizeof(PgBenchExpr));
+ int nfunctions = sizeof(PGBENCH_FUNCTIONS) / sizeof(PGBENCH_FUNCTIONS[0]);
+ int i;
+
+ expr->etype = ENODE_FUNCTION;
+ expr->u.function.function = PGBENCH_NONE;
+
+ for (i = 0; i < nfunctions; i++)
+ if (pg_strcasecmp(fname, PGBENCH_FUNCTIONS[i].fname) == 0)
+ expr->u.function.function = PGBENCH_FUNCTIONS[i].tag;
+
+ Assert(expr->u.function.function != PGBENCH_NONE);
+
+ expr->u.function.arg1 = arg1;
+ return expr;
+}
+
#include "exprscan.c"
diff --git a/contrib/pgbench/exprscan.l b/contrib/pgbench/exprscan.l
index 4c9229c..a276444 100644
--- a/contrib/pgbench/exprscan.l
+++ b/contrib/pgbench/exprscan.l
@@ -46,6 +46,7 @@ space [ \t\r\f]
")" { yycol += yyleng; return ')'; }
:[a-zA-Z0-9_]+ { yycol += yyleng; yylval.str = pg_strdup(yytext + 1); return VARIABLE; }
[0-9]+ { yycol += yyleng; yylval.ival = strtoint64(yytext); return INTEGER; }
+[a-zA-Z]+ { yycol += yyleng; yylval.str = pg_strdup(yytext); return FUNCTION; }
[\n] { yycol = 0; yyline++; }
{space} { yycol += yyleng; /* ignore */ }
diff --git a/contrib/pgbench/pgbench.c b/contrib/pgbench/pgbench.c
index 706fdf5..1e9604d 100644
--- a/contrib/pgbench/pgbench.c
+++ b/contrib/pgbench/pgbench.c
@@ -959,6 +959,26 @@ evaluateExpr(CState *st, PgBenchExpr *expr, int64 *retval)
return false;
}
+ case ENODE_FUNCTION:
+ {
+ switch (expr->u.function.function)
+ {
+ case PGBENCH_ABS:
+ {
+ int64 arg1;
+ if (!evaluateExpr(st, expr->u.function.arg1, &arg1))
+ return false;
+
+ *retval = arg1 > 0? arg1: -arg1;
+ return true;
+ }
+ default:
+ fprintf(stderr, "bad function (%d)",
+ expr->u.function.function);
+ return false;
+ }
+ }
+
default:
break;
}
diff --git a/contrib/pgbench/pgbench.h b/contrib/pgbench/pgbench.h
index 128bf11..8697c7b 100644
--- a/contrib/pgbench/pgbench.h
+++ b/contrib/pgbench/pgbench.h
@@ -15,12 +15,19 @@ typedef enum PgBenchExprType
{
ENODE_INTEGER_CONSTANT,
ENODE_VARIABLE,
- ENODE_OPERATOR
+ ENODE_OPERATOR,
+ ENODE_FUNCTION
} PgBenchExprType;
struct PgBenchExpr;
typedef struct PgBenchExpr PgBenchExpr;
+typedef enum PgBenchFunction
+{
+ PGBENCH_NONE,
+ PGBENCH_ABS
+} PgBenchFunction;
+
struct PgBenchExpr
{
PgBenchExprType etype;
@@ -40,6 +47,11 @@ struct PgBenchExpr
PgBenchExpr *lexpr;
PgBenchExpr *rexpr;
} operator;
+ struct
+ {
+ int function;
+ PgBenchExpr *arg1;
+ } function;
} u;
};
--
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