Extend userproxy test to check outputs

Currently just checks that initialization and self termination
actually happened.

Signed-off-by: Simo Sorce <simo@redhat.com>

tests/userproxytest.c

@@ -1,16 +1,20 @@
 /* Copyright (C) 2022 the GSS-PROXY contributors, see COPYING for license */
 
 #define _GNU_SOURCE
+#include <fcntl.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <sys/wait.h>
+#include <time.h>
 #include <unistd.h>
 
 char *srv_args[] = {
     "./gssproxy",
     "-u", "-i",
+    "-d", "--debug-level=1",
     "-s", "./testdir/userproxytest.sock",
     "--idle-timeout=3"
 };
@@ -54,34 +58,122 @@ int mock_activation_environment(void)
     return 0;
 }
 
+int wait_and_check_output(int outfd, int timeout)
+{
+    struct {
+        const char *match;
+        bool matched;
+    } checks[] = {
+        { "Initialization complete.", false },
+        { "Terminating, after idling", false },
+        { NULL, true }
+    };
+    time_t start = time(NULL);
+    time_t now = start;
+    useconds_t interval = 100 * 1000; /* 100 msec */
+    char outbuf[1024];
+    char *line;
+    FILE *out;
+    int ret;
+
+    /* make pipe non blocking */
+    ret = fcntl(outfd, F_SETFL, O_NONBLOCK);
+    if (ret) return -1;
+
+    out = fdopen(outfd, "r");
+    if (!out) return -1;
+
+    while (now < start + timeout) {
+        ret = usleep(interval);
+        if (ret) return -1;
+
+        line = fgets(outbuf, 1023, out);
+        if (line) {
+            for (int i = 0; checks[i].match != NULL; i++) {
+                if (strstr(line, checks[i].match)) {
+                    checks[i].matched = true;
+                }
+            }
+        }
+
+        now = time(NULL);
+    }
+
+    fclose(out);
+
+    for (int i = 0; checks[i].match != NULL; i++) {
+        if (checks[i].matched == false) return -1;
+    }
+
+    return 0;
+}
+
+int child(int outpipe[])
+{
+    int ret;
+
+    ret = mock_activation_environment();
+    if (ret) exit(EXIT_FAILURE);
+
+    close(outpipe[0]);
+    ret = dup2(outpipe[1], 2);
+    if (ret == -1) exit(EXIT_FAILURE);
+
+    execv("./gssproxy", srv_args);
+    exit(EXIT_FAILURE);
+}
+
 int main(int argc, const char *main_argv[])
 {
     pid_t proxy, w;
+    int outpipe[2];
     int ret;
 
     fprintf(stderr, "Test userproxy mode: ");
 
     ret = mock_activation_sockets();
-    if (ret) return -1;
+    if (ret) {
+        ret = EXIT_FAILURE;
+        goto done;
+    }
+
+    ret = pipe(outpipe);
+    if (ret) {
+        ret = EXIT_FAILURE;
+        goto done;
+    }
 
     proxy = fork();
-    if (proxy == -1) return -1;
+    if (proxy == -1) {
+        ret = EXIT_FAILURE;
+        goto done;
+    }
 
     if (proxy == 0) {
-        ret = mock_activation_environment();
-        if (ret) return -1;
-
-        execv("./gssproxy", srv_args);
-        return -1;
+        child(outpipe);
     }
 
-    sleep(6);
+    close(outpipe[1]);
+
+    ret = wait_and_check_output(outpipe[0], 6);
+    if (ret) {
+        ret = EXIT_FAILURE;
+        goto done;
+    }
 
     w = waitpid(-1, &ret, WNOHANG);
     if (w != proxy || ret != 0) {
+        ret = EXIT_FAILURE;
+        goto done;
+    }
+
+    ret = 0;
+
+done:
+    if (ret) {
         fprintf(stderr, "FAIL\n");
         fflush(stderr);
-        return -1;
+        return ret;
     }
 
     fprintf(stderr, "SUCCESS\n");