indent(1): Use bsearch() for looking up type keywords.

Reference:
f3b8e6e57f

Submitted by:	Piotr Stefaniak
Differential Revision: https://reviews.freebsd.org/D6966

usr.bin/indent/args.c

@@ -298,7 +298,7 @@ found:
 		char *str = strdup(param_start);
 		if (str == NULL)
 			err(1, NULL);
-		addkey(str, 4);
+		add_typename(str);
 	    }
 	    break;
 
@@ -342,6 +342,7 @@ add_typedefs_from_file(const char *str)
 {
     FILE *file;
     char line[BUFSIZ];
+    char *copy;
 
     if ((file = fopen(str, "r")) == NULL) {
 	fprintf(stderr, "indent: cannot open file %s\n", str);
@@ -349,8 +350,11 @@ add_typedefs_from_file(const char *str)
     }
     while ((fgets(line, BUFSIZ, file)) != NULL) {
 	/* Remove trailing whitespace */
-	*(line + strcspn(line, " \t\n\r")) = '\0';
-	addkey(strdup(line), 4);
+	line[strcspn(line, " \t\n\r")] = '\0';
+	if ((copy = strdup(line)) == NULL) {
+	    err(1, NULL);
+	}
+	add_typename(copy);
     }
     fclose(file);
 }

usr.bin/indent/indent.c

@@ -119,6 +119,7 @@ main(int argc, char **argv)
     tokenbuf = (char *) malloc(bufsize);
     if (tokenbuf == NULL)
 	err(1, NULL);
+    alloc_typenames();
     l_com = combuf + bufsize - 5;
     l_lab = labbuf + bufsize - 5;
     l_code = codebuf + bufsize - 5;

usr.bin/indent/indent.h

@@ -28,7 +28,8 @@
 __FBSDID("$FreeBSD$");
 #endif
 
-void	addkey(char *, int);
+void	add_typename(const char *);
+void	alloc_typenames(void);
 int	compute_code_target(void);
 int	compute_label_target(void);
 int	count_spaces(int, char *);

usr.bin/indent/lexi.c

@@ -64,42 +64,49 @@ struct templ {
     int         rwcode;
 };
 
-struct templ specials[16384] =
+/*
+ * This table has to be sorted alphabetically, because it'll be used in binary
+ * search. For the same reason, string must be the first thing in struct templ.
+ */
+struct templ specials[] =
 {
-    {"switch", 7},
-    {"case", 8},
     {"break", 9},
-    {"struct", 3},
-    {"union", 3},
-    {"enum", 3},
-    {"default", 8},
-    {"int", 4},
+    {"case", 8},
     {"char", 4},
-    {"float", 4},
-    {"double", 4},
-    {"long", 4},
-    {"short", 4},
-    {"typedef", 4},
-    {"unsigned", 4},
-    {"register", 4},
-    {"static", 4},
-    {"global", 4},
-    {"extern", 4},
-    {"void", 4},
     {"const", 4},
-    {"volatile", 4},
-    {"goto", 9},
-    {"return", 9},
-    {"if", 5},
-    {"while", 5},
-    {"for", 5},
-    {"else", 6},
+    {"default", 8},
     {"do", 6},
-    {"sizeof", 2},
+    {"double", 4},
+    {"else", 6},
+    {"enum", 3},
+    {"extern", 4},
+    {"float", 4},
+    {"for", 5},
+    {"global", 4},
+    {"goto", 9},
+    {"if", 5},
+    {"int", 4},
+    {"long", 4},
     {"offsetof", 1},
-    {0, 0}
+    {"register", 4},
+    {"return", 9},
+    {"short", 4},
+    {"sizeof", 2},
+    {"static", 4},
+    {"struct", 3},
+    {"switch", 7},
+    {"typedef", 4},
+    {"union", 3},
+    {"unsigned", 4},
+    {"void", 4},
+    {"volatile", 4},
+    {"while", 5}
 };
 
+const char **typenames;
+int         typename_count;
+int         typename_top = -1;
+
 char        chartype[128] =
 {				/* this is used to facilitate the decision of
 				 * what type (alphanumeric, operator) each
@@ -122,6 +129,12 @@ char        chartype[128] =
     1, 1, 1, 0, 3, 0, 3, 0
 };
 
+static int
+strcmp_type(const void *e1, const void *e2)
+{
+    return (strcmp(e1, *(const char * const *)e2));
+}
+
 int
 lexi(void)
 {
@@ -150,9 +163,6 @@ lexi(void)
 	/*
 	 * we have a character or number
 	 */
-	const char *j;		/* used for searching thru list of
-				 *
-				 * reserved words */
 	struct templ *p;
 
 	if (isdigit(*buf_ptr) || (buf_ptr[0] == '.' && isdigit(buf_ptr[1]))) {
@@ -247,37 +257,24 @@ lexi(void)
 	last_code = ident;	/* Remember that this is the code we will
 				 * return */
 
-	if (auto_typedefs) {
-	    const char *q = s_token;
-	    size_t q_len = strlen(q);
-	    /* Check if we have an "_t" in the end */
-	    if (q_len > 2 &&
-	        (strcmp(q + q_len - 2, "_t") == 0)) {
-	        ps.keyword = 4;	/* a type name */
-		ps.last_u_d = true;
-	        goto found_auto_typedef;
-	    }
-	}
+	p = bsearch(s_token,
+	    specials,
+	    sizeof(specials) / sizeof(specials[0]),
+	    sizeof(specials[0]),
+	    strcmp_type);
+	if (p == NULL) {	/* not a special keyword... */
+	    char *u;
 
-	/*
-	 * This loop will check if the token is a keyword.
-	 */
-	for (p = specials; (j = p->rwd) != NULL; p++) {
-	    const char *q = s_token;	/* point at scanned token */
-	    if (*j++ != *q++ || *j++ != *q++)
-		continue;	/* This test depends on the fact that
-				 * identifiers are always at least 1 character
-				 * long (ie. the first two bytes of the
-				 * identifier are always meaningful) */
-	    if (q[-1] == 0)
-		break;		/* If its a one-character identifier */
-	    while (*q++ == *j)
-		if (*j++ == 0)
-		    goto found_keyword;	/* I wish that C had a multi-level
-					 * break... */
-	}
-	if (p->rwd) {		/* we have a keyword */
-    found_keyword:
+	    /* ... so maybe a type_t or a typedef */
+	    if ((auto_typedefs && ((u = strrchr(s_token, '_')) != NULL) &&
+	        strcmp(u, "_t") == 0) || (typename_top >= 0 &&
+		  bsearch(s_token, typenames, typename_top + 1,
+		    sizeof(typenames[0]), strcmp_type))) {
+		ps.keyword = 4;	/* a type name */
+		ps.last_u_d = true;
+	        goto found_typename;
+	    }
+	} else {			/* we have a keyword */
 	    ps.keyword = p->rwcode;
 	    ps.last_u_d = true;
 	    switch (p->rwcode) {
@@ -295,7 +292,7 @@ lexi(void)
 		/* FALLTHROUGH */
 
 	    case 4:		/* one of the declaration keywords */
-	    found_auto_typedef:
+	    found_typename:
 		if (ps.p_l_follow) {
 		    /* inside parens: cast, param list, offsetof or sizeof */
 		    ps.cast_mask |= (1 << ps.p_l_follow) & ~ps.not_cast_mask;
@@ -583,24 +580,43 @@ stop_lit:
     return (code);
 }
 
-/*
- * Add the given keyword to the keyword table, using val as the keyword type
- */
 void
-addkey(char *key, int val)
+alloc_typenames(void)
 {
-    struct templ *p = specials;
-    while (p->rwd)
-	if (p->rwd[0] == key[0] && strcmp(p->rwd, key) == 0)
-	    return;
-	else
-	    p++;
-    if (p >= specials + sizeof(specials) / sizeof(specials[0])) {
-	fprintf(stderr, "indent: typedef table overflow\n");
-	exit(1);
-    }
-    p->rwd = key;
-    p->rwcode = val;
-    p[1].rwd = NULL;
-    p[1].rwcode = 0;
+
+    typenames = (const char **)malloc(sizeof(typenames[0]) *
+        (typename_count = 16));
+    if (typenames == NULL)
+	err(1, NULL);
+}
+
+void
+add_typename(const char *key)
+{
+    int comparison;
+
+    if (typename_top + 1 >= typename_count) {
+	typenames = realloc((void *)typenames,
+	    sizeof(typenames[0]) * (typename_count *= 2));
+	if (typenames == NULL)
+	    err(1, NULL);
+    }
+    if (typename_top == -1)
+	typenames[++typename_top] = key;
+    else if ((comparison = strcmp(key, typenames[typename_top])) >= 0) {
+	/* take advantage of sorted input */
+	if (comparison != 0)	/* remove duplicates */
+	    typenames[++typename_top] = key;
+    }
+    else {
+	int p;
+
+	for (p = 0; (comparison = strcmp(key, typenames[p])) >= 0; p++)
+	    /* find place for the new key */;
+	if (comparison == 0)	/* remove duplicates */
+	    return;
+	memmove(&typenames[p + 1], &typenames[p],
+	    sizeof(typenames[0]) * (++typename_top - p));
+	typenames[p] = key;
+    }
 }