mpv/libmpdemux/realrtsp/asmrp.c

678 lines
11 KiB
C

/*
* This file was ported to MPlayer from xine CVS asmrp.c,v 1.2 2002/12/17 16:49:48
*/
/*
* Copyright (C) 2002 the xine project
*
* This file is part of xine, a free video player.
*
* xine is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* xine is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*
*
* a parser for real's asm rules
*
* grammar for these rules:
*
rule_book = { rule }
rule = ( '#' condition { ',' assignment } | [ assignment {',' assignment} ]) ';'
assignment = id '=' const
const = ( number | string )
condition = comp_expr { ( '&&' | '||' ) comp_expr }
comp_expr = operand { ( '<' | '<=' | '==' | '>=' | '>' ) operand }
operand = ( '$' id | num | '(' condition ')' )
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
/*
#define LOG
*/
#define ASMRP_SYM_NONE 0
#define ASMRP_SYM_EOF 1
#define ASMRP_SYM_NUM 2
#define ASMRP_SYM_ID 3
#define ASMRP_SYM_STRING 4
#define ASMRP_SYM_HASH 10
#define ASMRP_SYM_SEMICOLON 11
#define ASMRP_SYM_COMMA 12
#define ASMRP_SYM_EQUALS 13
#define ASMRP_SYM_AND 14
#define ASMRP_SYM_OR 15
#define ASMRP_SYM_LESS 16
#define ASMRP_SYM_LEQ 17
#define ASMRP_SYM_GEQ 18
#define ASMRP_SYM_GREATER 19
#define ASMRP_SYM_DOLLAR 20
#define ASMRP_SYM_LPAREN 21
#define ASMRP_SYM_RPAREN 22
#define ASMRP_MAX_ID 1024
#define ASMRP_MAX_SYMTAB 10
typedef struct {
char *id;
int v;
} asmrp_sym_t;
typedef struct {
/* public part */
int sym;
int num;
char str[ASMRP_MAX_ID];
/* private part */
char *buf;
int pos;
char ch;
asmrp_sym_t sym_tab[ASMRP_MAX_SYMTAB];
int sym_tab_num;
} asmrp_t;
static asmrp_t *asmrp_new () {
asmrp_t *p;
p = malloc (sizeof (asmrp_t));
p->sym_tab_num = 0;
p->sym = ASMRP_SYM_NONE;
return p;
}
static void asmrp_dispose (asmrp_t *p) {
int i;
for (i=0; i<p->sym_tab_num; i++)
free (p->sym_tab[i].id);
free (p);
}
static void asmrp_getch (asmrp_t *p) {
p->ch = p->buf[p->pos];
p->pos++;
#ifdef LOG
printf ("%c\n", p->ch);
#endif
}
static void asmrp_init (asmrp_t *p, const char *str) {
p->buf = strdup (str);
p->pos = 0;
asmrp_getch (p);
}
static void asmrp_number (asmrp_t *p) {
int num;
num = 0;
while ( (p->ch>='0') && (p->ch<='9') ) {
num = num*10 + (p->ch - '0');
asmrp_getch (p);
}
p->sym = ASMRP_SYM_NUM;
p->num = num;
}
static void asmrp_string (asmrp_t *p) {
int l;
l = 0;
while ( (p->ch!='"') && (p->ch>=32) ) {
p->str[l] = p->ch;
l++;
asmrp_getch (p);
}
p->str[l]=0;
if (p->ch=='"')
asmrp_getch (p);
p->sym = ASMRP_SYM_STRING;
}
static void asmrp_identifier (asmrp_t *p) {
int l;
l = 0;
while ( ((p->ch>='A') && (p->ch<='z'))
|| ((p->ch>='0') && (p->ch<='9'))) {
p->str[l] = p->ch;
l++;
asmrp_getch (p);
}
p->str[l]=0;
p->sym = ASMRP_SYM_ID;
}
#ifdef LOG
static void asmrp_print_sym (asmrp_t *p) {
printf ("symbol: ");
switch (p->sym) {
case ASMRP_SYM_NONE:
printf ("NONE\n");
break;
case ASMRP_SYM_EOF:
printf ("EOF\n");
break;
case ASMRP_SYM_NUM:
printf ("NUM %d\n", p->num);
break;
case ASMRP_SYM_ID:
printf ("ID '%s'\n", p->str);
break;
case ASMRP_SYM_STRING:
printf ("STRING \"%s\"\n", p->str);
break;
case ASMRP_SYM_HASH:
printf ("#\n");
break;
case ASMRP_SYM_SEMICOLON:
printf (";\n");
break;
case ASMRP_SYM_COMMA:
printf (",\n");
break;
case ASMRP_SYM_EQUALS:
printf ("==\n");
break;
case ASMRP_SYM_AND:
printf ("&&\n");
break;
case ASMRP_SYM_OR:
printf ("||\n");
break;
case ASMRP_SYM_LESS:
printf ("<\n");
break;
case ASMRP_SYM_LEQ:
printf ("<=\n");
break;
case ASMRP_SYM_GEQ:
printf (">=\n");
break;
case ASMRP_SYM_GREATER:
printf (">\n");
break;
case ASMRP_SYM_DOLLAR:
printf ("$\n");
break;
case ASMRP_SYM_LPAREN:
printf ("(\n");
break;
case ASMRP_SYM_RPAREN:
printf (")\n");
break;
default:
printf ("unknown symbol %d\n", p->sym);
}
}
#endif
static void asmrp_get_sym (asmrp_t *p) {
while (p->ch <= 32) {
if (p->ch == 0) {
p->sym = ASMRP_SYM_EOF;
return;
}
asmrp_getch (p);
}
if (p->ch == '\\')
asmrp_getch (p);
switch (p->ch) {
case '#':
p->sym = ASMRP_SYM_HASH;
asmrp_getch (p);
break;
case ';':
p->sym = ASMRP_SYM_SEMICOLON;
asmrp_getch (p);
break;
case ',':
p->sym = ASMRP_SYM_COMMA;
asmrp_getch (p);
break;
case '=':
p->sym = ASMRP_SYM_EQUALS;
asmrp_getch (p);
if (p->ch=='=')
asmrp_getch (p);
break;
case '&':
p->sym = ASMRP_SYM_AND;
asmrp_getch (p);
if (p->ch=='&')
asmrp_getch (p);
break;
case '|':
p->sym = ASMRP_SYM_OR;
asmrp_getch (p);
if (p->ch=='|')
asmrp_getch (p);
break;
case '<':
p->sym = ASMRP_SYM_LESS;
asmrp_getch (p);
if (p->ch=='=') {
p->sym = ASMRP_SYM_LEQ;
asmrp_getch (p);
}
break;
case '>':
p->sym = ASMRP_SYM_GREATER;
asmrp_getch (p);
if (p->ch=='=') {
p->sym = ASMRP_SYM_GEQ;
asmrp_getch (p);
}
break;
case '$':
p->sym = ASMRP_SYM_DOLLAR;
asmrp_getch (p);
break;
case '(':
p->sym = ASMRP_SYM_LPAREN;
asmrp_getch (p);
break;
case ')':
p->sym = ASMRP_SYM_RPAREN;
asmrp_getch (p);
break;
case '"':
asmrp_getch (p);
asmrp_string (p);
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
asmrp_number (p);
break;
default:
asmrp_identifier (p);
}
#ifdef LOG
asmrp_print_sym (p);
#endif
}
static int asmrp_find_id (asmrp_t *p, char *s) {
int i;
for (i=0; i<p->sym_tab_num; i++) {
if (!strcmp (s, p->sym_tab[i].id))
return i;
}
return -1;
}
static int asmrp_set_id (asmrp_t *p, char *s, int v) {
int i;
i = asmrp_find_id (p, s);
if (i<0) {
i = p->sym_tab_num;
p->sym_tab_num++;
p->sym_tab[i].id = strdup (s);
#ifdef LOG
printf ("new symbol '%s'\n", s);
#endif
}
p->sym_tab[i].v = v;
#ifdef LOG
printf ("symbol '%s' assigned %d\n", s, v);
#endif
return i;
}
static int asmrp_condition (asmrp_t *p) ;
static int asmrp_operand (asmrp_t *p) {
int i, ret;
#ifdef LOG
printf ("operand\n");
#endif
ret = 0;
switch (p->sym) {
case ASMRP_SYM_DOLLAR:
asmrp_get_sym (p);
if (p->sym != ASMRP_SYM_ID) {
printf ("error: identifier expected.\n");
abort();
}
i = asmrp_find_id (p, p->str);
if (i<0) {
printf ("error: unknown identifier %s\n", p->str);
}
ret = p->sym_tab[i].v;
asmrp_get_sym (p);
break;
case ASMRP_SYM_NUM:
ret = p->num;
asmrp_get_sym (p);
break;
case ASMRP_SYM_LPAREN:
asmrp_get_sym (p);
ret = asmrp_condition (p);
if (p->sym != ASMRP_SYM_RPAREN) {
printf ("error: ) expected.\n");
abort();
}
asmrp_get_sym (p);
break;
default:
printf ("syntax error, $ number or ( expected\n");
abort();
}
#ifdef LOG
printf ("operand done, =%d\n", ret);
#endif
return ret;
}
static int asmrp_comp_expression (asmrp_t *p) {
int a;
#ifdef LOG
printf ("comp_expression\n");
#endif
a = asmrp_operand (p);
while ( (p->sym == ASMRP_SYM_LESS)
|| (p->sym == ASMRP_SYM_LEQ)
|| (p->sym == ASMRP_SYM_EQUALS)
|| (p->sym == ASMRP_SYM_GEQ)
|| (p->sym == ASMRP_SYM_GREATER) ) {
int op = p->sym;
int b;
asmrp_get_sym (p);
b = asmrp_operand (p);
switch (op) {
case ASMRP_SYM_LESS:
a = a<b;
break;
case ASMRP_SYM_LEQ:
a = a<=b;
break;
case ASMRP_SYM_EQUALS:
a = a==b;
break;
case ASMRP_SYM_GEQ:
a = a>=b;
break;
case ASMRP_SYM_GREATER:
a = a>b;
break;
}
}
#ifdef LOG
printf ("comp_expression done = %d\n", a);
#endif
return a;
}
static int asmrp_condition (asmrp_t *p) {
int a;
#ifdef LOG
printf ("condition\n");
#endif
a = asmrp_comp_expression (p);
while ( (p->sym == ASMRP_SYM_AND) || (p->sym == ASMRP_SYM_OR) ) {
int op, b;
op = p->sym;
asmrp_get_sym (p);
b = asmrp_comp_expression (p);
switch (op) {
case ASMRP_SYM_AND:
a = a & b;
break;
case ASMRP_SYM_OR:
a = a | b;
break;
}
}
#ifdef LOG
printf ("condition done = %d\n", a);
#endif
return a;
}
static void asmrp_assignment (asmrp_t *p) {
#ifdef LOG
printf ("assignment\n");
#endif
if (p->sym == ASMRP_SYM_COMMA || p->sym == ASMRP_SYM_SEMICOLON) {
#ifdef LOG
printf ("empty assignment\n");
#endif
return;
}
if (p->sym != ASMRP_SYM_ID) {
printf ("error: identifier expected\n");
abort ();
}
asmrp_get_sym (p);
if (p->sym != ASMRP_SYM_EQUALS) {
printf ("error: = expected\n");
abort ();
}
asmrp_get_sym (p);
if ( (p->sym != ASMRP_SYM_NUM) && (p->sym != ASMRP_SYM_STRING)
&& (p->sym != ASMRP_SYM_ID)) {
printf ("error: number or string expected\n");
abort ();
}
asmrp_get_sym (p);
#ifdef LOG
printf ("assignment done\n");
#endif
}
static int asmrp_rule (asmrp_t *p) {
int ret;
#ifdef LOG
printf ("rule\n");
#endif
ret = 1;
if (p->sym == ASMRP_SYM_HASH) {
asmrp_get_sym (p);
ret = asmrp_condition (p);
while (p->sym == ASMRP_SYM_COMMA) {
asmrp_get_sym (p);
asmrp_assignment (p);
}
} else if (p->sym != ASMRP_SYM_SEMICOLON) {
asmrp_assignment (p);
while (p->sym == ASMRP_SYM_COMMA) {
asmrp_get_sym (p);
asmrp_assignment (p);
}
}
#ifdef LOG
printf ("rule done = %d\n", ret);
#endif
if (p->sym != ASMRP_SYM_SEMICOLON) {
printf ("semicolon expected.\n");
abort ();
}
asmrp_get_sym (p);
return ret;
}
static int asmrp_eval (asmrp_t *p, int *matches) {
int rule_num, num_matches;
#ifdef LOG
printf ("eval\n");
#endif
asmrp_get_sym (p);
rule_num = 0; num_matches = 0;
while (p->sym != ASMRP_SYM_EOF) {
if (asmrp_rule (p)) {
#ifdef LOG
printf ("rule #%d is true\n", rule_num);
#endif
matches[num_matches] = rule_num;
num_matches++;
}
rule_num++;
}
matches[num_matches] = -1;
return num_matches;
}
int asmrp_match (const char *rules, int bandwidth, int *matches) {
asmrp_t *p;
int num_matches;
p = asmrp_new ();
asmrp_init (p, rules);
asmrp_set_id (p, "Bandwidth", bandwidth);
asmrp_set_id (p, "OldPNMPlayer", 0);
num_matches = asmrp_eval (p, matches);
asmrp_dispose (p);
return num_matches;
}