sqltext.c

編譯器的相關東西原始碼

/*
 *	Text handling routines for simple embedded SQL
 */

#include <stdio.h>
#include <string.h>
extern FILE *yyout;	/* lex output file */

char save_buf[2000];	/* buffer for SQL command */
char *savebp;		/* current buffer pointer */

#define NPARAM	20	/* max params per function */
char *varnames[NPARAM];	/* parameter names */

/* start an embedded command after EXEC SQL */
start_save(void)
{

	savebp = save_buf;
} /* start_save */

/* save a SQL token */
save_str(char *s)
{

	strcpy(savebp, s);
	savebp += strlen(s);
} /* save_str */

/* save a parameter reference */
save_param(char *n)
{
	int i;
	char pbuf[10];

	/* look up the variable name in the table */
	
	for(i = 1; i < NPARAM; i++) {
		if(!varnames[i]) {

			/* not there, enter it */
			varnames[i] = strdup(n);
			break;
		}

		if(!strcmp(varnames[i],n))
			break;	/* already present */
	}

	if(i >= NPARAM) {
		yyerror("Too many parameter references");
		exit(1);
	}

	/* save #n referece by variable number */
	sprintf(pbuf, " #%d", i);
	save_str(pbuf);

} /* save_param */

/* end of SQL command, now write it out */
end_sql(void)
{
	int i;
	register char *cp;

	savebp--;	/* back over the closing semicolon */

	/* call exec_sql function */
	
	fprintf(yyout, "exec_sql(\"");

	/* write out saved buffer as a big C string
	 * starting new lines as needed
	 */
	
	for(cp = save_buf, i = 20; cp < savebp; cp++, i++) {
		if(i > 70) {	/* need new line */
			fprintf(yyout, "\\\n");
			i = 0;
		}
		putc(*cp, yyout);
	}
	putc('"', yyout);

	/* pass address of every referenced variable */
	for(i = 1; i < NPARAM; i++) {
		if(!varnames[i])
			break;
		fprintf(yyout, ",\n\t&%s", varnames[i]);
		free(varnames[i]);
		varnames[i] = 0;
	}

	fprintf(yyout, ");\n");

	/* return scanner to regular mode */
	un_sql();

} /* end_sql */