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allow more complex expressions

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zimoch
2018-04-19 16:01:48 +02:00
parent b7aaedfd23
commit 430d163fc2
1 changed files with 125 additions and 67 deletions
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runScript.c
+125 -67
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@@ -51,11 +51,11 @@ epicsShareFunc int epicsShareAPI iocshCmd(const char *cmd);
int runScriptDebug=0;
static int parseExpr(const char** pp, int* v);
static int parseExpr(const char** pp, long* v, int op);
static int parseValue(const char** pp, int* v)
static int parseValue(const char** pp, long* v)
{
int val;
long val;
const char *p = *pp;
char o;
@@ -65,32 +65,35 @@ static int parseValue(const char** pp, int* v)
* Allowed chars after a number: operators, closing parenthesis, whitespace, quotes, end of string
*/
do {
while (isspace((unsigned char)*p)) p++;
} while (*p == '+' && p++);
/* first look for value */
while (isspace((unsigned char)*p)) p++;
o = *p;
if (memchr("-~!", o, 3))
if (memchr("+-~!", o, 4))
{
/* handle unary operators */
p++;
if (!parseValue(&p, &val)) return 0;
if (!parseValue(&p, &val)) return 0; /* no valid value */
if (o == '-') val=-val;
else if (o == '~') val=~val;
else if (o == '!') val=!val;
}
else if (o == '(')
{
/* handle sub-expression */
if (runScriptDebug > 1) printf("parseValue: subexpression '%s'\n", p);
p++;
if (!parseExpr(&p, &val)) return 0;
if (parseExpr(&p, &val, 0) < 0) return 0; /* no valid expression */
while (isspace((unsigned char)*p)) p++;
if (*p++ != ')') return 0;
if (*p++ != ')') return 0; /* missing ) */
}
else
{
/* get number */
char* e;
val = strtol(p, &e, 0);
if (e == p) return 0; /* no number */
if (*e && !isspace((unsigned char)*e) && !strchr("+-*/%|&^?)'\",", *e))
if (isalpha((unsigned char)*p))
{
/* followed by rubbish */
if (runScriptDebug > 1) printf("parseValue: bail out from '%s' at '%s'\n", *pp, e);
@@ -98,55 +101,110 @@ static int parseValue(const char** pp, int* v)
}
p = e;
}
if (runScriptDebug > 1) printf("parseValue: '%.*s' = %d rest '%s'\n", (int)(p-*pp), *pp, val, p);
if (runScriptDebug > 1) printf("parseValue: '%.*s' = %ld rest '%s'\n", (int)(p-*pp), *pp, val, p);
*pp = p;
*v = val;
return 1;
}
static int parseExpr(const char** pp, int* v)
static long ipow(long base, long exp)
{
long v;
if (exp < 0) return 0;
if (exp == 0) return 1;
v = base;
while (--exp) v *= base; /* optimize this! */
return v;
}
struct {char str[3]; char pr;} ops[] = {
{"",0},
{"**",2},
{"*", 3},{"/",3},{"%",3},
{"+",4},{"-",4},
{"<<",5},{">>>",5},{">>",5},
{"<=>",6},{"<=",6},{">=",6},{"<",6},{">",6},
{"==",7},{"!=",7},
{"&&",11},{"||",12},
{"&",8},{"^",9},{"|",10}
};
static int startsWith(const char* p, const char* s)
{
int i = 0;
while (*s) { i++; if (*p++ != *s++) return 0; }
return i;
}
static int parseOp(const char** pp)
{
const char *p = *pp;
const char *q;
int sum = 0, val, val2;
char o;
int o, l;
/* An expression is a value optionally followed by an operator and another value.
* Outer loop: low priority operators + -
* Inner loop: high priority operators * / %
* A value is a number or an expression in ().
* Allowed chars after a expression: quotes, space, end of string
*/
do {
if (!parseValue(&p, &val)) return 0;
q = p;
while (isspace((unsigned char)*q)) q++;
o = *q;
while (memchr("*/%&|^", o, 6))
{
q++;
if (!parseValue(&q, &val2)) return 0;
if (o == '*') val *= val2;
else if (o == '&') val &= val2;
else if (o == '|') val |= val2;
else if (o == '^') val ^= val2;
else if (val2 == 0) val = 0; /* define division by zero as 0 */
else if (o == '/') val /= val2;
else val %= val2;
p = q;
o = *p;
}
sum += val;
} while (o == '+' || o == '-');
if (*p == '?')
while (isspace((unsigned char)*p)) p++;
if (runScriptDebug > 1) printf("parseOp: check %s\n", p);
if (ispunct((unsigned char)*p))
{
p++;
sum = (sum != 0);
for (o = 1; o < (int)(sizeof(ops)/sizeof(ops[0])); o++)
{
if ((l = startsWith(p, ops[o].str)))
{
/* operator found */
if (runScriptDebug > 1) printf("parseOp: %.3s\n", ops[0].str);
*pp = p+l;
return o;
}
}
}
if (runScriptDebug > 1) printf("parseExpr: '%.*s' = %d\n", (int)(p-*pp), *pp, sum);
if (runScriptDebug > 1) printf("parseOp: end\n");
return 0;
}
static int parseExpr(const char** pp, long* v, int o)
{
const char *p = *pp;
long val = 0;
long val2;
int o2 = o;
int pr = ops[o].pr;
if (runScriptDebug > 1) printf("parseExpr: o = %.3s\n", ops[o].str);
do {
if (!parseValue(&p, &val2)) return -1;
if ((o2 = parseOp(&p)) != 0 && ops[o2].pr < pr)
if ((o2 = parseExpr(&p, &val2, o2)) < 0) return -1;
if (runScriptDebug > 1) printf("parseExpr: %ld %.3s %ld\n", val, ops[o].str, val2);
switch(o)
{
case 0: val = val2; break;
case 1: val = ipow(val, val2); break;
case 2: val *= val2; break;
case 3: val /= val2; break;
case 4: val %= val2; break;
case 5: val += val2; break;
case 6: val -= val2; break;
case 7: val <<= val2; break;
case 8: val = (unsigned long)val >> val2; break;
case 9: val >>= val2; break;
case 10: val = val < val2 ? -1 : val == val2 ? 0 : 1; break;
case 11: val = val <= val2; break;
case 12: val = val >= val2; break;
case 13: val = val < val2; break;
case 14: val = val > val2; break;
case 15: val = val == val2; break;
case 16: val = val != val2; break;
case 17: val = val && val2; break;
case 18: val = val || val2; break;
case 19: val &= val2; break;
case 20: val ^= val2; break;
case 21: val |= val2; break;
}
o = o2;
} while (o && pr <= ops[o].pr);
if (runScriptDebug > 1) printf("parseExpr: result %ld\n", val);
*pp = p;
*v = sum;
return 1;
*v = val;
return o;
}
const char* getFormat(const char** pp)
@@ -154,23 +212,25 @@ const char* getFormat(const char** pp)
static char format [20];
const char* p = *pp;
unsigned int i = 1;
if (runScriptDebug > 1) printf ("getFormat %s\n", p);
if (runScriptDebug > 1) printf("getFormat %s\n", p);
if ((format[0] = *p++) == '%')
{
while (i < sizeof(format) && memchr(" #-+0", *p, 5))
format[i++] = *p++;
while (i < sizeof(format) && *p >= '0' && *p <= '9')
format[i++] = *p++;
if (i < sizeof(format))
format[i++] = 'l';
if (i < sizeof(format) && memchr("diouxXc", *p, 7))
{
format[i++] = *p++;
format[i] = 0;
*pp = p;
if (runScriptDebug > 1) printf ("format=%s\n", format);
if (runScriptDebug > 1) printf("format = '%s'\n", format);
return format;
}
}
if (runScriptDebug > 1) printf ("no format\n");
if (runScriptDebug > 1) printf("no format\n");
return NULL;
}
@@ -327,20 +387,18 @@ int runScript(const char* filename, const char* args)
const char* r;
char* s;
char* w;
int val;
long val;
*x++ = 0;
r = x;
w = line_raw;
while (*r)
{
/* Resolve integer expressions:
* Any free standing expression.
* Any expression in parentheses () embedded in an unquoted word.
/* Resolve integer expressions that are either free standing
* or in parentheses () embedded in an unquoted word.
* Do not resolve expressions in single or double quoted strings.
* An expression optionally starts with a format such as %x.
* It consists of integer numbers (including 0x prefixed hex numbers),
* unary (+-!~) and binary (+-*%/) oprators and parentheses ().
* An expression optionally starts with a integer format such as %x.
* It consists of integer numbers, operators and parentheses ().
*/
s = w;
if (*r == '"' || *r == '\'')
@@ -353,15 +411,15 @@ int runScript(const char* filename, const char* args)
}
if (*r) *w++ = *r++;
*w = 0;
if (runScriptDebug > 1) printf ("quoted string %s\n", s);
if (runScriptDebug > 1) printf("quoted string %s\n", s);
}
else if (*r == '%')
{
/* formatted expression */
const char* r2 = r;
const char* f;
if (runScriptDebug > 1) printf ("formatted expression after '%s'\n", s);
if ((f = getFormat(&r2)) && parseExpr(&r2, &val))
if (runScriptDebug > 1) printf("formatted expression after '%s'\n", s);
if ((f = getFormat(&r2)) && parseExpr(&r2, &val, 0) == 0)
{
r = r2;
if (*s == '(' && *r2++ == ')')
@@ -370,15 +428,15 @@ int runScript(const char* filename, const char* args)
r = r2;
}
w += sprintf(w, f , val);
if (runScriptDebug > 1) printf ("formatted expression %s\n", s);
if (runScriptDebug > 1) printf("formatted expression %s\n", s);
}
}
else if (parseExpr(&r, &val))
else if (parseExpr(&r, &val, 0) == 0)
{
/* unformatted expression */
w += sprintf(w, "%d", val);
w += sprintf(w, "%ld", val);
*w = 0;
if (runScriptDebug > 1) printf ("simple expression %s\n", s);
if (runScriptDebug > 1) printf("simple expression %s\n", s);
}
else if (*r == ',')
{
@@ -391,7 +449,7 @@ int runScript(const char* filename, const char* args)
*w++ = *r++;
} while (*r && !strchr("%(\"', \t\n", *r));
*w = 0;
if (runScriptDebug > 1) printf ("plain word '%s'\n", s);
if (runScriptDebug > 1) printf("plain word '%s'\n", s);
}
/* copy space */
while (isspace((unsigned char)*r)) *w++ = *r++;