From a0ee703ee27b476c2bf4e02d6392c1f4d9c51764 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?T=C3=B3th=20J=C3=A1nos?= <gomba007@gmail.com>
Date: Wed, 13 Nov 2024 11:04:18 +0100
Subject: [PATCH] Implement `-U` for FreeBSD.

Tested on FreeBSD 14.1.
Takes part of #2072.
---
 doc/man.md.j2  |  2 +-
 src/conky.cc   |  8 ++++----
 src/freebsd.cc | 36 ++++++++++++++++++++++++++++++++++++
 src/freebsd.h  |  2 ++
 src/main.cc    | 12 ++++++------
 5 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/doc/man.md.j2 b/doc/man.md.j2
index d564e89b8..85d1eda48 100644
--- a/doc/man.md.j2
+++ b/doc/man.md.j2
@@ -163,7 +163,7 @@ file.
 **-U \| \--unique**
 
 :   Conky won't start if another Conky process is already running. Implemented
-    only for Linux.
+    only for Linux and FreeBSD.
 
 **-v \| -V \| \--version** 
 
diff --git a/src/conky.cc b/src/conky.cc
index 44399cc54..8e2f4c0d0 100644
--- a/src/conky.cc
+++ b/src/conky.cc
@@ -2107,9 +2107,9 @@ void set_current_config() {
 /* : means that character before that takes an argument */
 const char *getopt_string =
     "vVqdDSs:t:u:i:hc:p:"
-#if defined(__linux__)
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
     "U"
-#endif
+#endif /* Linux || FreeBSD */
 #ifdef BUILD_X11
     "x:y:w:a:X:m:f:"
 #ifdef OWN_WINDOW
@@ -2140,9 +2140,9 @@ const struct option longopts[] = {
 #endif /* BUILD_X11 */
     {"text", 1, nullptr, 't'},          {"interval", 1, nullptr, 'u'},
     {"pause", 1, nullptr, 'p'},
-#if defined(__linux__)
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
     {"unique", 0, nullptr, 'U'},
-#endif /* Linux */
+#endif /* Linux || FreeBSD */
     {nullptr, 0, nullptr, 0}
 };
 
diff --git a/src/freebsd.cc b/src/freebsd.cc
index 0243c4624..f5913c55c 100644
--- a/src/freebsd.cc
+++ b/src/freebsd.cc
@@ -46,6 +46,7 @@
 #include <devstat.h>
 #include <ifaddrs.h>
 #include <limits.h>
+#include <paths.h>
 #include <unistd.h>
 
 #include <dev/acpica/acpiio.h>
@@ -778,3 +779,38 @@ void print_sysctlbyname(struct text_object *obj, char *p,
     snprintf(p, p_max_size, "%lu", (unsigned long)val[0]);
   }
 }
+
+/******************************************
+ * Check if more than one conky process   *
+ * is running                             *
+ ******************************************/
+
+bool is_conky_already_running(void) {
+  kvm_t *kd;
+  struct kinfo_proc *kp;
+  char errbuf[_POSIX2_LINE_MAX];
+  int entries = -1;
+  int instances = 0;
+
+  kd = kvm_openfiles(NULL, _PATH_DEVNULL, NULL, O_RDONLY, errbuf);
+  if (kd == NULL) {
+    NORM_ERR("%s\n", errbuf);
+    return false;
+  }
+
+  kp = kvm_getprocs(kd, KERN_PROC_ALL, 0, &entries);
+  if ((kp == NULL && errno != ESRCH) || (kp != NULL && entries < 0)) {
+    NORM_ERR("%s\n", kvm_geterr(kd));
+    goto cleanup;
+  }
+
+  for (int i = 0; i < entries && instances < 2; ++i) {
+    if (!strcmp("conky", kp[i].ki_comm)) {
+        ++instances;
+    }
+  }
+
+cleanup:
+  kvm_close(kd);
+  return instances > 1;
+}
diff --git a/src/freebsd.h b/src/freebsd.h
index f2baf9785..d64cf569c 100644
--- a/src/freebsd.h
+++ b/src/freebsd.h
@@ -47,4 +47,6 @@ int get_entropy_avail(unsigned int *);
 int get_entropy_poolsize(unsigned int *);
 void print_sysctlbyname(struct text_object *, char *, unsigned int);
 
+bool is_conky_already_running(void);
+
 #endif /*FREEBSD_H_*/
diff --git a/src/main.cc b/src/main.cc
index 327ef59fd..909d12cfc 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -273,9 +273,9 @@ static void print_help(const char *prog_name) {
          " (and quit)\n"
          "   -p, --pause=SECS          pause for SECS seconds at startup "
          "before doing anything\n"
-#if defined(__linux__)
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
          "   -U, --unique              only one conky process can be created\n"
-#endif /* Linux */
+#endif /* Linux || FreeBSD */
          , prog_name);
 }
 
@@ -358,22 +358,22 @@ int main(int argc, char **argv) {
         window.window = strtol(optarg, nullptr, 0);
         break;
 #endif /* BUILD_X11 */
-#if defined(__linux__)
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
       case 'U':
         unique_process = true;
         break;
-#endif /* Linux */
+#endif /* Linux || FreeBSD */
       case '?':
         return EXIT_FAILURE;
     }
   }
 
-#if defined(__linux__)
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
   if (unique_process && is_conky_already_running()) {
     NORM_ERR("already running");
     return 0;
   }
-#endif /* Linux */
+#endif /* Linux || FreeBSD */
 
   try {
     set_current_config();