[hackers] [sbase] Use SLIST_* instead of TAILQ_* in grep(1) || sin

[git]

commit afa2e6ec54b911a85f4d497d2afd4cfe0af0d636
Author: sin <s...@2f30.org>
Date:   Mon Nov 17 10:59:11 2014 +0000

    Use SLIST_* instead of TAILQ_* in grep(1)
    
    The order of evaluation is unspecified by POSIX so we do not need
    to process the patterns in-order.

diff --git a/grep.c b/grep.c
index b2bf051..dc379d5 100644
--- a/grep.c
+++ b/grep.c
@@ -24,10 +24,10 @@ static char mode = 0;
 struct pattern {
        char *pattern;
        regex_t preg;
-       TAILQ_ENTRY(pattern) entry;
+       SLIST_ENTRY(pattern) entry;
 };
 
-static TAILQ_HEAD(phead, pattern) phead;
+static SLIST_HEAD(phead, pattern) phead;
 
 static void
 usage(void)
@@ -38,11 +38,11 @@ usage(void)
 int
 main(int argc, char *argv[])
 {
-       struct pattern *pnode, *tmp;
+       struct pattern *pnode;
        int i, m, flags = REG_NOSUB, match = NoMatch;
        FILE *fp;
 
-       TAILQ_INIT(&phead);
+       SLIST_INIT(&phead);
 
        ARGBEGIN {
        case 'E':
@@ -85,9 +85,8 @@ main(int argc, char *argv[])
        }
 
        /* Compile regex for all search patterns */
-       TAILQ_FOREACH(pnode, &phead, entry) {
+       SLIST_FOREACH(pnode, &phead, entry)
                enregcomp(Error, &pnode->preg, pnode->pattern, flags);
-       }
        many = (argc > 1);
        if (argc == 0) {
                match = grep(stdin, "<stdin>");
@@ -104,8 +103,9 @@ main(int argc, char *argv[])
                        fclose(fp);
                }
        }
-       TAILQ_FOREACH_SAFE(pnode, &phead, entry, tmp) {
-               TAILQ_REMOVE(&phead, pnode, entry);
+       while (!SLIST_EMPTY(&phead)) {
+               pnode = SLIST_FIRST(&phead);
+               SLIST_REMOVE_HEAD(&phead, entry);
                regfree(&pnode->preg);
                free(pnode->pattern);
                free(pnode);
@@ -120,7 +120,7 @@ addpattern(const char *pattern)
 
        pnode = emalloc(sizeof(*pnode));
        pnode->pattern = estrdup(pattern);
-       TAILQ_INSERT_TAIL(&phead, pnode, entry);
+       SLIST_INSERT_HEAD(&phead, pnode, entry);
 }
 
 static int
@@ -136,7 +136,7 @@ grep(FILE *fp, const char *str)
                /* Remove the trailing newline if one is present. */
                if (len && buf[len - 1] == '\n')
                        buf[len - 1] = '\0';
-               TAILQ_FOREACH(pnode, &phead, entry) {
+               SLIST_FOREACH(pnode, &phead, entry) {
                        if (regexec(&pnode->preg, buf, 0, NULL, 0) ^ vflag)
                                continue;
                        switch (mode) {