In lemon, add "%if" and "%else" and allow boolean expressions as the
argument to "%if", "%ifdef", and "%ifndef".
FossilOrigin-Name: 951d22b72f80de9e23df645abcc3d88ca1a275b46ea23b84152ef48716922b37
diff --git a/tool/lemon.c b/tool/lemon.c
index 8dcf651..40e4e28 100644
--- a/tool/lemon.c
+++ b/tool/lemon.c
@@ -423,6 +423,7 @@
int nlookaheadtab; /* Number of entries in yy_lookahead[] */
int tablesize; /* Total table size of all tables in bytes */
int basisflag; /* Print only basis configurations */
+ int printPreprocessed; /* Show preprocessor output on stdout */
int has_fallback; /* True if any %fallback is seen in the grammar */
int nolinenosflag; /* True if #line statements should not be printed */
char *argv0; /* Name of the program */
@@ -1636,12 +1637,14 @@
static int nolinenosflag = 0;
static int noResort = 0;
static int sqlFlag = 0;
+ static int printPP = 0;
static struct s_options options[] = {
{OPT_FLAG, "b", (char*)&basisflag, "Print only the basis in report."},
{OPT_FLAG, "c", (char*)&compress, "Don't compress the action table."},
{OPT_FSTR, "d", (char*)&handle_d_option, "Output directory. Default '.'"},
{OPT_FSTR, "D", (char*)handle_D_option, "Define an %ifdef macro."},
+ {OPT_FLAG, "E", (char*)&printPP, "Print input file after preprocessing."},
{OPT_FSTR, "f", 0, "Ignored. (Placeholder for -f compiler options.)"},
{OPT_FLAG, "g", (char*)&rpflag, "Print grammar without actions."},
{OPT_FSTR, "I", 0, "Ignored. (Placeholder for '-I' compiler options.)"},
@@ -1686,11 +1689,12 @@
lem.filename = OptArg(0);
lem.basisflag = basisflag;
lem.nolinenosflag = nolinenosflag;
+ lem.printPreprocessed = printPP;
Symbol_new("$");
/* Parse the input file */
Parse(&lem);
- if( lem.errorcnt ) exit(lem.errorcnt);
+ if( lem.printPreprocessed || lem.errorcnt ) exit(lem.errorcnt);
if( lem.nrule==0 ){
fprintf(stderr,"Empty grammar.\n");
exit(1);
@@ -2779,13 +2783,108 @@
}
}
+/* The text in the input is part of the argument to an %ifdef or %ifndef.
+** Evaluate the text as a boolean expression. Return true or false.
+*/
+static int eval_preprocessor_boolean(char *z, int lineno){
+ int neg = 0;
+ int res = 0;
+ int okTerm = 1;
+ int i;
+ for(i=0; z[i]!=0; i++){
+ if( ISSPACE(z[i]) ) continue;
+ if( z[i]=='!' ){
+ if( !okTerm ) goto pp_syntax_error;
+ neg = !neg;
+ continue;
+ }
+ if( z[i]=='|' && z[i+1]=='|' ){
+ if( okTerm ) goto pp_syntax_error;
+ if( res ) return 1;
+ i++;
+ okTerm = 1;
+ continue;
+ }
+ if( z[i]=='&' && z[i+1]=='&' ){
+ if( okTerm ) goto pp_syntax_error;
+ if( !res ) return 0;
+ i++;
+ okTerm = 1;
+ continue;
+ }
+ if( z[i]=='(' ){
+ int k;
+ int n = 1;
+ if( !okTerm ) goto pp_syntax_error;
+ for(k=i+1; z[k]; k++){
+ if( z[k]==')' ){
+ n--;
+ if( n==0 ){
+ z[k] = 0;
+ res = eval_preprocessor_boolean(&z[i+1], -1);
+ z[k] = ')';
+ if( res<0 ){
+ i = i-res;
+ goto pp_syntax_error;
+ }
+ i = k;
+ break;
+ }
+ }else if( z[k]=='(' ){
+ n++;
+ }else if( z[k]==0 ){
+ i = k;
+ goto pp_syntax_error;
+ }
+ }
+ if( neg ){
+ res = !res;
+ neg = 0;
+ }
+ okTerm = 0;
+ continue;
+ }
+ if( ISALPHA(z[i]) ){
+ int j, k, n;
+ if( !okTerm ) goto pp_syntax_error;
+ for(k=i+1; ISALNUM(z[k]) || z[k]=='_'; k++){}
+ n = k - i;
+ res = 0;
+ for(j=0; j<nDefine; j++){
+ if( strncmp(azDefine[j],&z[i],n)==0 && azDefine[j][n]==0 ){
+ res = 1;
+ break;
+ }
+ }
+ i = k-1;
+ if( neg ){
+ res = !res;
+ neg = 0;
+ }
+ okTerm = 0;
+ continue;
+ }
+ goto pp_syntax_error;
+ }
+ return res;
+
+pp_syntax_error:
+ if( lineno>0 ){
+ fprintf(stderr, "%%if syntax error on line %d.\n", lineno);
+ fprintf(stderr, " %.*s <-- syntax error here\n", i+1, z);
+ exit(1);
+ }else{
+ return -(i+1);
+ }
+}
+
/* Run the preprocessor over the input file text. The global variables
** azDefine[0] through azDefine[nDefine-1] contains the names of all defined
** macros. This routine looks for "%ifdef" and "%ifndef" and "%endif" and
** comments them out. Text in between is also commented out as appropriate.
*/
static void preprocess_input(char *z){
- int i, j, k, n;
+ int i, j, k;
int exclude = 0;
int start = 0;
int lineno = 1;
@@ -2801,21 +2900,33 @@
}
}
for(j=i; z[j] && z[j]!='\n'; j++) z[j] = ' ';
- }else if( (strncmp(&z[i],"%ifdef",6)==0 && ISSPACE(z[i+6]))
- || (strncmp(&z[i],"%ifndef",7)==0 && ISSPACE(z[i+7])) ){
+ }else if( strncmp(&z[i],"%else",5)==0 && ISSPACE(z[i+5]) ){
+ if( exclude==1){
+ exclude = 0;
+ for(j=start; j<i; j++) if( z[j]!='\n' ) z[j] = ' ';
+ }else if( exclude==0 ){
+ exclude = 1;
+ start = i;
+ start_lineno = lineno;
+ }
+ for(j=i; z[j] && z[j]!='\n'; j++) z[j] = ' ';
+ }else if( strncmp(&z[i],"%ifdef ",7)==0
+ || strncmp(&z[i],"%if ",4)==0
+ || strncmp(&z[i],"%ifndef ",8)==0 ){
if( exclude ){
exclude++;
}else{
- for(j=i+7; ISSPACE(z[j]); j++){}
- for(n=0; z[j+n] && !ISSPACE(z[j+n]); n++){}
- exclude = 1;
- for(k=0; k<nDefine; k++){
- if( strncmp(azDefine[k],&z[j],n)==0 && lemonStrlen(azDefine[k])==n ){
- exclude = 0;
- break;
- }
- }
- if( z[i+3]=='n' ) exclude = !exclude;
+ int isNot;
+ int iBool;
+ for(j=i; z[j] && !ISSPACE(z[j]); j++){}
+ iBool = j;
+ isNot = (j==i+7);
+ while( z[j] && z[j]!='\n' ){ j++; }
+ k = z[j];
+ z[j] = 0;
+ exclude = eval_preprocessor_boolean(&z[iBool], lineno);
+ z[j] = k;
+ if( !isNot ) exclude = !exclude;
if( exclude ){
start = i;
start_lineno = lineno;
@@ -2883,6 +2994,10 @@
/* Make an initial pass through the file to handle %ifdef and %ifndef */
preprocess_input(filebuf);
+ if( gp->printPreprocessed ){
+ printf("%s\n", filebuf);
+ return;
+ }
/* Now scan the text of the input file */
lineno = 1;