X-Git-Url: https://secure.softndesign.org/git/?a=blobdiff_plain;f=parser.c;h=1d35b4c44785dc85eee79b7600b2c62eebb40910;hb=89cf095594de27bde3e3be007d255cad56ab0eca;hp=0391246e5e6b9334e9b545d7b6e44a91baebf9ac;hpb=11cda8d79e2b44c25c26e58f6bfe7c0bb421ee19;p=calc.git diff --git a/parser.c b/parser.c index 0391246..1d35b4c 100644 --- a/parser.c +++ b/parser.c @@ -1,4 +1,5 @@ #include +#include #include #include "debug.h" @@ -46,30 +47,55 @@ element_t *newelement (func_t function, int nbops, int prio) /* functions */ -#define NB_OPERATORS 5 +#define NB_OPERATORS 6 keyword_t operators[NB_OPERATORS] = { { "+\t", Add, 2, 1, 1}, { "-\t", Sub, 2, 1, 1}, { "*", Mul, 2, 1, 2}, { "/", Div, 2, 1, 2}, - { "^", Pow, 2, 1, 3} + { "%", Mod, 2, 1, 3}, + { "^", Pow, 2, 1, 4} }; -#define NB_FUNCTIONS 7 +#define NB_FUNCTIONS 9 keyword_t functions[NB_FUNCTIONS] = { - { "sqrt", Sqr, 1, 4, 4}, - { "pow", Pow, 2, 3, 4}, - { "cos", Cos, 1, 3, 4}, - { "sin", Sin, 1, 3, 4}, - { "atan", Atn, 1, 4, 4}, - { "exp", Exp, 1, 3, 4}, - { "log", Log, 1, 3, 4} + { "sqrt", Sqr, 1, 4, 5}, + { "pow", Pow, 2, 3, 5}, + { "cos", Cos, 1, 3, 5}, + { "sin", Sin, 1, 3, 5}, + { "atan", Atn, 1, 4, 5}, + { "exp", Exp, 1, 3, 5}, + { "log", Log, 1, 3, 5}, + { "quit", Qui, 0, 4, 5}, + { "help", Hel, 0, 4, 5} }; +/* subparser function */ + +element_t *subparser (element_t **proot, char **pstr, func_t func, int nbops, int prio) +{ + element_t *new = newelement (func, nbops, prio); + if (new == NULL) { + return ERROR_OP; + } + new->ops[0] = *proot; + new->ops[1] = parser (*pstr, pstr, new->prio); + if (new->ops[1] == ERROR_OP) { + return ERROR_OP; + } + *proot = newelement (Val, 1, 5); + if (*proot == ERROR_OP) { + return ERROR_OP; + } + (*proot)->ops[0] = new; + + return *proot; +} + /* parser function */ -element_t *parser (char *str, char **next) +element_t *parser (char *str, char **next, int prio) { element_t *root = NULL; int i; @@ -96,7 +122,7 @@ element_t *parser (char *str, char **next) if (root) { do { found = 0; - new = parser (str + 1, &str); + new = parser (str + 1, &str, 0); if (new == ERROR_OP) { return ERROR_OP; } @@ -112,11 +138,11 @@ element_t *parser (char *str, char **next) } } while (*str == ','); } else { - root = newelement (Val, 1, 4); + root = newelement (Val, 1, 5); if (root == NULL) { return ERROR_OP; } - new = parser (str + 1, &str); + new = parser (str + 1, &str, 0); if ((new == ERROR_OP) || (*str == ',')) { return ERROR_OP; } @@ -142,29 +168,23 @@ element_t *parser (char *str, char **next) keyword_t *operator = operators + i; if (codecmp (operator->keyword, str) == 0) { VERBOSE (DEBUG, PRINTOUT ("start processing operator\n")); - str += operator->offset; if (root) { + if ((prio) && (prio > operator->prio)) { + VERBOSE (DEBUG, PRINTOUT ("stop because operator priority\n")); + *next = str; + return root; + } + str += operator->offset; VERBOSE (INFO, PRINTOUT ("Oper: %d\n", operator->func)); - new = newelement (operator->func, operator->nbops, operator->prio); - if (new == NULL) { + if (subparser (&root, &str, operator->func, operator->nbops, operator->prio) == ERROR_OP) { return ERROR_OP; } - element_t *next = parser (str, &str); - if (next == ERROR_OP) { + } else if (*str == '-') { + new = newelement (Sig, 1, 9); + if (new == NULL) { return ERROR_OP; } - VERBOSE (DEBUG, PRINTOUT ("Priorities: %d > %d -> %s\n", new->prio, next->prio, (new->prio > next->prio) ? "True" : "False")); - if (new->prio > next->prio) { - VERBOSE (DEBUG, PRINTOUT ("Take account of priority\n")); - new->ops[0] = root; - new->ops[1] = next->ops[0]; - next->ops[0] = new; - root = next; - } else { - new->ops[0] = root; - new->ops[1] = next; - root = new; - } + root = new; } else { return ERROR_OP; } @@ -212,29 +232,30 @@ element_t *parser (char *str, char **next) float value = strtof (str, &pt); VERBOSE (INFO, PRINTOUT ("Value: %f\n", value)); if (str != pt) { - new = newelement (Val, 1, 4); - if (new == NULL) { - return ERROR_OP; - } - new->value = value; if (root == NULL) { + new = newelement (Val, 1, 5); + if (new == NULL) { + return ERROR_OP; + } + new->value = value; root = new; + str = pt; } else if (root->func == Val) { if ((*str == '+') || (*str == '-')) { - element_t *add = newelement (Add, 2, 1); - if (add == NULL) { + if ((prio) && (prio > 1)) { + VERBOSE (DEBUG, PRINTOUT ("stop because operator priority\n")); + *next = str; + return root; + } + if (subparser (&root, &str, Add, 2, 1) == ERROR_OP) { return ERROR_OP; } - add->ops[0] = root; - add->ops[1] = new; - root = add; } else { return ERROR_OP; } } else { return ERROR_OP; } - str = pt; found = 1; } VERBOSE (DEBUG, PRINTOUT ("stop processing value\n")); @@ -271,11 +292,12 @@ void print_element (element_t *root, int level) switch (root->func) { case Val: func = "Value"; break; - case Set: func = "Set"; break; + case Sig: func = "Sign"; break; case Add: func = "Addition"; break; case Sub: func = "Subtraction"; break; case Mul: func = "Multiplication"; break; case Div: func = "Division"; break; + case Mod: func = "Modulo"; break; case Pow: func = "Power"; break; case Sqr: func = "Square Root"; break; case Cos: func = "Cosine"; break; @@ -283,6 +305,8 @@ void print_element (element_t *root, int level) case Atn: func = "Arc Tangent"; break; case Log: func = "Logarithm"; break; case Exp: func = "Exponantial"; break; + case Qui: func = "Quit"; break; + case Hel: func = "Help"; break; } PRINTOUT ("Function: %s\n", func); @@ -299,4 +323,118 @@ void print_element (element_t *root, int level) } } +/* quit function */ + +void quit (void) +{ + PRINTOUT ("bye\n"); + exit (0); +} + +/* help message */ + +void help (void) +{ + PRINTOUT ("calc is a simple calculator\n\n"); + PRINTOUT ("supported operators:\n"); + PRINTOUT (" + - * / % ^\n\n"); + PRINTOUT ("supported functions:\n"); + PRINTOUT (" pow sqrt cos sin atan log exp\n\n"); + PRINTOUT ("miscellaneous functions:\n"); + PRINTOUT (" quit help\n"); +} + +/* evaluate element tree */ + +#define MASK_SUB 0x1 +#define MASK_DIV 0x2 + +double evaluate_element (element_t *root, char mask) +{ + double op0 = 0, op1 = 0; + char nextmask = mask; + + if ((root == NULL) || (root == ERROR_OP)) { + VERBOSE (WARNING, PRINTOUT ("error while evaluating\n")); + return 0; + } + + /* mask to manage sub operator sub and div */ + switch (root->func) { + case Add: + nextmask &= ~MASK_SUB; + nextmask &= ~MASK_DIV; + break; + case Sub: + nextmask |= MASK_SUB; + nextmask &= ~MASK_DIV; + break; + case Mul: + nextmask &= ~MASK_DIV; + break; + case Div: + nextmask |= MASK_DIV; + break; + default: + nextmask = mask; + } + + switch (root->func) { + case Val: + case Sig: + op0 = (root->ops[0]) ? evaluate_element (root->ops[0], nextmask) : root->value; + break; + case Add: + case Sub: + case Mul: + case Div: + case Mod: + case Pow: + if (root->ops[1]) { + op1 = evaluate_element (root->ops[1], nextmask); + } else { + VERBOSE (WARNING, PRINTOUT ("error while evaluating (op[1])\n")); + return 0; + } + /* fallthrough */ + case Sqr: + case Cos: + case Sin: + case Atn: + case Log: + case Exp: + if (root->ops[0]) { + op0 = evaluate_element (root->ops[0], 0); + } else { + VERBOSE (WARNING, PRINTOUT ("error while evaluating (op[0])\n")); + return 0; + } + break; + case Qui: + case Hel: + break; + } + + switch (root->func) { + case Val: return op0; + case Sig: return -op0; + case Add: return ((mask & MASK_SUB) == 0) ? op0 + op1 : op0 - op1; + case Sub: return ((mask & MASK_SUB) == 0) ? op0 - op1 : op0 + op1; + case Mul: return ((mask & MASK_DIV) == 0) ? op0 * op1 : op0 / op1; + case Div: return ((mask & MASK_DIV) == 0) ? op0 / op1 : op0 * op1; + case Mod: return fmod (op0, op1); + case Pow: return pow (op0, op1); + case Sqr: return sqrt (op0); + case Cos: return cos (op0); + case Sin: return sin (op0); + case Atn: return atan (op0); + case Log: return log (op0); + case Exp: return exp (op0); + case Qui: quit (); break; + case Hel: help (); break; + } + + return 0; +} + /* vim: set ts=4 sw=4 et: */