Fixed the build on MacOS (and others).

@alejandro-colomar reported that the build was broken on MacOS

cc  -o build/unitd -pipe -fPIC -fvisibility=hidden -O -W -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -fstrict-aliasing -Wstrict-overflow=5 -Wmissing-prototypes -Werror -g   \
		build/src/nxt_main.o  build/libnxt.a \
		    \
                      \
                    -L/usr/local/Cellar/pcre2/10.40/lib -lpcre2-8
Undefined symbols for architecture x86_64:
  "_nxt_fs_mkdir_parent", referenced from:
      _nxt_runtime_pid_file_create in libnxt.a(nxt_runtime.o)
      _nxt_runtime_controller_socket in libnxt.a(nxt_controller.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [build/unitd] Error 1

This was due to commit 57fc920 ("Socket: Created control socket & pid file
directories.").

This happened because this commit introduced the usage of
nxt_fs_mkdir_parent() in core code which uses nxt_fs_mkdir(), both of
these are defined in src/nxt_fs.c. It turns out however that this file
doesn't get built on MacOS (or any system that isn't Linux or that
lacks a FreeBSD compatible nmount(2) system call) due to the following

In auto/sources we have

  if [ $NXT_HAVE_ROOTFS = YES ]; then
      NXT_LIB_SRCS="$NXT_LIB_SRCS src/nxt_fs.c"
  fi

NXT_HAVE_ROOTFS is set in auto/isolation

  If [ $NXT_HAVE_MOUNT = YES -a $NXT_HAVE_UNMOUNT = YES ]; then
      NXT_HAVE_ROOTFS=YES

      cat << END >> $NXT_AUTO_CONFIG_H
  #ifndef NXT_HAVE_ISOLATION_ROOTFS
  #define NXT_HAVE_ISOLATION_ROOTFS  1
  #endif
  END

  fi

While we do have a check for a generic umount(2) which is found on
MacOS, for mount(2) we currently only check for the Linux mount(2) and
FreeBSD nmount(2) system calls. So NXT_HAVE_ROOTFS is set to NO on MacOS
and we don't build src/nxt_fs.c

This fixes the immediate build issue by taking the mount/umount OS
support out of nxt_fs.c into a new nxt_fs_mount.c file which is guarded
by the above while we now build nxt_fs.c unconditionally.

This should fix the build on any _supported_ system.

Reported-by: Alejandro Colomar <alx@nginx.com>
Fixes: 57fc920 ("Socket: Created control socket & pid file directories.")
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

5 files changed, 279 insertions, 257 deletions

diff --git a/src/nxt_fs.c b/src/nxt_fs.c
index 35850798..a467da98 100644
--- a/src/nxt_fs.c
+++ b/src/nxt_fs.c
@@ -4,235 +4,10 @@
 
 #include <nxt_main.h>
 
-#if (NXT_HAVE_FREEBSD_NMOUNT)
-#include <sys/param.h>
-#include <sys/uio.h>
-#endif
-
 
 static nxt_int_t nxt_fs_mkdir(const u_char *dir, mode_t mode);
 
 
-#if (NXT_HAVE_LINUX_MOUNT)
-
-nxt_int_t
-nxt_fs_mount(nxt_task_t *task, nxt_fs_mount_t *mnt)
-{
-    int            rc;
-    const char     *fsname;
-    unsigned long  flags;
-
-    flags = 0;
-
-    switch (mnt->type) {
-    case NXT_FS_BIND:
-        if (nxt_slow_path(mnt->flags != 0)) {
-            nxt_log(task, NXT_LOG_WARN,
-                    "bind mount ignores additional flags");
-        }
-
-        fsname = "bind";
-        flags = MS_BIND | MS_REC;
-        break;
-
-    case NXT_FS_PROC:
-        fsname = "proc";
-        goto getflags;
-
-    case NXT_FS_TMP:
-        fsname = "tmpfs";
-        goto getflags;
-
-    default:
-        fsname = (const char *) mnt->name;
-
-    getflags:
-
-        if (mnt->flags & NXT_FS_FLAGS_NODEV) {
-            flags |= MS_NODEV;
-        }
-
-        if (mnt->flags & NXT_FS_FLAGS_NOEXEC) {
-            flags |= MS_NOEXEC;
-        }
-
-        if (mnt->flags & NXT_FS_FLAGS_NOSUID) {
-            flags |= MS_NOSUID;
-        }
-
-        if (!(mnt->flags & NXT_FS_FLAGS_NOTIME)) {
-            flags |= MS_RELATIME;
-        }
-    }
-
-    rc = mount((const char *) mnt->src, (const char *) mnt->dst, fsname, flags,
-               mnt->data);
-
-    if (nxt_slow_path(rc < 0)) {
-        nxt_alert(task, "mount(\"%s\", \"%s\", \"%s\", %ul, \"%s\") %E",
-                  mnt->src, mnt->dst, fsname, flags, mnt->data, nxt_errno);
-
-        return NXT_ERROR;
-    }
-
-    return NXT_OK;
-}
-
-#elif (NXT_HAVE_FREEBSD_NMOUNT)
-
-nxt_int_t
-nxt_fs_mount(nxt_task_t *task, nxt_fs_mount_t *mnt)
-{
-    int           flags;
-    u_char        *data, *p, *end;
-    size_t        iovlen;
-    nxt_int_t     ret;
-    const char    *fsname;
-    struct iovec  iov[128];
-    char          errmsg[256];
-
-    if (nxt_slow_path((mnt->flags & NXT_FS_FLAGS_NODEV) && !mnt->builtin)) {
-        nxt_alert(task, "nmount(2) doesn't support \"nodev\" option");
-
-        return NXT_ERROR;
-    }
-
-    flags = 0;
-
-    switch (mnt->type) {
-    case NXT_FS_BIND:
-        fsname = "nullfs";
-        break;
-
-    case NXT_FS_PROC:
-        fsname = "procfs";
-        goto getflags;
-
-    case NXT_FS_TMP:
-        fsname = "tmpfs";
-        goto getflags;
-
-    default:
-        fsname = (const char *) mnt->name;
-
-    getflags:
-
-        if (mnt->flags & NXT_FS_FLAGS_NOEXEC) {
-            flags |= MNT_NOEXEC;
-        }
-
-        if (mnt->flags & NXT_FS_FLAGS_NOSUID) {
-            flags |= MNT_NOSUID;
-        }
-
-        if (mnt->flags & NXT_FS_FLAGS_NOTIME) {
-            flags |= MNT_NOATIME;
-        }
-
-        if (mnt->flags & NXT_FS_FLAGS_RDONLY) {
-            flags |= MNT_RDONLY;
-        }
-    }
-
-    iov[0].iov_base = (void *) "fstype";
-    iov[0].iov_len = 7;
-    iov[1].iov_base = (void *) fsname;
-    iov[1].iov_len = nxt_strlen(fsname) + 1;
-    iov[2].iov_base = (void *) "fspath";
-    iov[2].iov_len = 7;
-    iov[3].iov_base = (void *) mnt->dst;
-    iov[3].iov_len = nxt_strlen(mnt->dst) + 1;
-    iov[4].iov_base = (void *) "target";
-    iov[4].iov_len = 7;
-    iov[5].iov_base = (void *) mnt->src;
-    iov[5].iov_len = nxt_strlen(mnt->src) + 1;
-    iov[6].iov_base = (void *) "errmsg";
-    iov[6].iov_len = 7;
-    iov[7].iov_base = (void *) errmsg;
-    iov[7].iov_len = sizeof(errmsg);
-
-    iovlen = 8;
-
-    data = NULL;
-
-    if (mnt->data != NULL) {
-        data = (u_char *) nxt_strdup(mnt->data);
-        if (nxt_slow_path(data == NULL)) {
-            return NXT_ERROR;
-        }
-
-        end = data - 1;
-
-        do {
-            p = end + 1;
-            end = nxt_strchr(p, '=');
-            if (end == NULL) {
-                break;
-            }
-
-            *end = '\0';
-
-            iov[iovlen].iov_base = (void *) p;
-            iov[iovlen].iov_len = (end - p) + 1;
-
-            iovlen++;
-
-            p = end + 1;
-
-            end = nxt_strchr(p, ',');
-            if (end != NULL) {
-                *end = '\0';
-            }
-
-            iov[iovlen].iov_base = (void *) p;
-            iov[iovlen].iov_len = nxt_strlen(p) + 1;
-
-            iovlen++;
-
-        } while (end != NULL && nxt_nitems(iov) > (iovlen + 2));
-    }
-
-    ret = NXT_OK;
-
-    if (nxt_slow_path(nmount(iov, iovlen, flags) < 0)) {
-        nxt_alert(task, "nmount(%p, %d, 0) %s", iov, iovlen, errmsg);
-        ret = NXT_ERROR;
-    }
-
-    if (data != NULL) {
-        free(data);
-    }
-
-    return ret;
-}
-
-#endif
-
-
-#if (NXT_HAVE_LINUX_UMOUNT2)
-
-void
-nxt_fs_unmount(const u_char *path)
-{
-    if (nxt_slow_path(umount2((const char *) path, MNT_DETACH) < 0)) {
-        nxt_thread_log_error(NXT_LOG_WARN, "umount2(%s, MNT_DETACH) %E",
-                             path, nxt_errno);
-    }
-}
-
-#elif (NXT_HAVE_UNMOUNT)
-
-void
-nxt_fs_unmount(const u_char *path)
-{
-    if (nxt_slow_path(unmount((const char *) path, MNT_FORCE) < 0)) {
-        nxt_thread_log_error(NXT_LOG_WARN, "unmount(%s) %E", path, nxt_errno);
-    }
-}
-
-#endif
-
-
 nxt_int_t
 nxt_fs_mkdir_all(const u_char *dir, mode_t mode)
 {
diff --git a/src/nxt_fs.h b/src/nxt_fs.h
index af9585b8..c8868d80 100644
--- a/src/nxt_fs.h
+++ b/src/nxt_fs.h
@@ -6,40 +6,8 @@
 #define _NXT_FS_H_INCLUDED_
 
 
-typedef enum {
-    NXT_FS_UNKNOWN = 0,
-    NXT_FS_BIND,
-    NXT_FS_TMP,
-    NXT_FS_PROC,
-    NXT_FS_LAST,
-} nxt_fs_type_t;
-
-
-typedef enum {
-    NXT_FS_FLAGS_NOSUID   = 1 << 0,
-    NXT_FS_FLAGS_NOEXEC   = 1 << 1,
-    NXT_FS_FLAGS_NOTIME   = 1 << 2,
-    NXT_FS_FLAGS_NODEV    = 1 << 3,
-    NXT_FS_FLAGS_RDONLY   = 1 << 4,
-} nxt_fs_flags_t;
-
-
-typedef struct {
-    u_char          *src;
-    u_char          *dst;
-    nxt_fs_type_t   type;
-    u_char          *name;
-    nxt_fs_flags_t  flags;
-    u_char          *data;
-    nxt_uint_t      builtin;  /* 1-bit */
-    nxt_uint_t      deps;     /* 1-bit */
-} nxt_fs_mount_t;
-
-
 nxt_int_t nxt_fs_mkdir_parent(const u_char *path, mode_t mode);
 nxt_int_t nxt_fs_mkdir_all(const u_char *dir, mode_t mode);
-nxt_int_t nxt_fs_mount(nxt_task_t *task, nxt_fs_mount_t *mnt);
-void nxt_fs_unmount(const u_char *path);
 
 
 #endif  /* _NXT_FS_H_INCLUDED_ */
diff --git a/src/nxt_fs_mount.c b/src/nxt_fs_mount.c
new file mode 100644
index 00000000..d9b384e4
--- /dev/null
+++ b/src/nxt_fs_mount.c
@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) NGINX, Inc.
+ */
+
+#include <nxt_main.h>
+
+#if (NXT_HAVE_FREEBSD_NMOUNT)
+#include <sys/param.h>
+#include <sys/uio.h>
+#endif
+
+
+#if (NXT_HAVE_LINUX_MOUNT)
+
+nxt_int_t
+nxt_fs_mount(nxt_task_t *task, nxt_fs_mount_t *mnt)
+{
+    int            rc;
+    const char     *fsname;
+    unsigned long  flags;
+
+    flags = 0;
+
+    switch (mnt->type) {
+    case NXT_FS_BIND:
+        if (nxt_slow_path(mnt->flags != 0)) {
+            nxt_log(task, NXT_LOG_WARN,
+                    "bind mount ignores additional flags");
+        }
+
+        fsname = "bind";
+        flags = MS_BIND | MS_REC;
+        break;
+
+    case NXT_FS_PROC:
+        fsname = "proc";
+        goto getflags;
+
+    case NXT_FS_TMP:
+        fsname = "tmpfs";
+        goto getflags;
+
+    default:
+        fsname = (const char *) mnt->name;
+
+    getflags:
+
+        if (mnt->flags & NXT_FS_FLAGS_NODEV) {
+            flags |= MS_NODEV;
+        }
+
+        if (mnt->flags & NXT_FS_FLAGS_NOEXEC) {
+            flags |= MS_NOEXEC;
+        }
+
+        if (mnt->flags & NXT_FS_FLAGS_NOSUID) {
+            flags |= MS_NOSUID;
+        }
+
+        if (!(mnt->flags & NXT_FS_FLAGS_NOTIME)) {
+            flags |= MS_RELATIME;
+        }
+    }
+
+    rc = mount((const char *) mnt->src, (const char *) mnt->dst, fsname, flags,
+               mnt->data);
+
+    if (nxt_slow_path(rc < 0)) {
+        nxt_alert(task, "mount(\"%s\", \"%s\", \"%s\", %ul, \"%s\") %E",
+                  mnt->src, mnt->dst, fsname, flags, mnt->data, nxt_errno);
+
+        return NXT_ERROR;
+    }
+
+    return NXT_OK;
+}
+
+#elif (NXT_HAVE_FREEBSD_NMOUNT)
+
+nxt_int_t
+nxt_fs_mount(nxt_task_t *task, nxt_fs_mount_t *mnt)
+{
+    int           flags;
+    u_char        *data, *p, *end;
+    size_t        iovlen;
+    nxt_int_t     ret;
+    const char    *fsname;
+    struct iovec  iov[128];
+    char          errmsg[256];
+
+    if (nxt_slow_path((mnt->flags & NXT_FS_FLAGS_NODEV) && !mnt->builtin)) {
+        nxt_alert(task, "nmount(2) doesn't support \"nodev\" option");
+
+        return NXT_ERROR;
+    }
+
+    flags = 0;
+
+    switch (mnt->type) {
+    case NXT_FS_BIND:
+        fsname = "nullfs";
+        break;
+
+    case NXT_FS_PROC:
+        fsname = "procfs";
+        goto getflags;
+
+    case NXT_FS_TMP:
+        fsname = "tmpfs";
+        goto getflags;
+
+    default:
+        fsname = (const char *) mnt->name;
+
+    getflags:
+
+        if (mnt->flags & NXT_FS_FLAGS_NOEXEC) {
+            flags |= MNT_NOEXEC;
+        }
+
+        if (mnt->flags & NXT_FS_FLAGS_NOSUID) {
+            flags |= MNT_NOSUID;
+        }
+
+        if (mnt->flags & NXT_FS_FLAGS_NOTIME) {
+            flags |= MNT_NOATIME;
+        }
+
+        if (mnt->flags & NXT_FS_FLAGS_RDONLY) {
+            flags |= MNT_RDONLY;
+        }
+    }
+
+    iov[0].iov_base = (void *) "fstype";
+    iov[0].iov_len = 7;
+    iov[1].iov_base = (void *) fsname;
+    iov[1].iov_len = nxt_strlen(fsname) + 1;
+    iov[2].iov_base = (void *) "fspath";
+    iov[2].iov_len = 7;
+    iov[3].iov_base = (void *) mnt->dst;
+    iov[3].iov_len = nxt_strlen(mnt->dst) + 1;
+    iov[4].iov_base = (void *) "target";
+    iov[4].iov_len = 7;
+    iov[5].iov_base = (void *) mnt->src;
+    iov[5].iov_len = nxt_strlen(mnt->src) + 1;
+    iov[6].iov_base = (void *) "errmsg";
+    iov[6].iov_len = 7;
+    iov[7].iov_base = (void *) errmsg;
+    iov[7].iov_len = sizeof(errmsg);
+
+    iovlen = 8;
+
+    data = NULL;
+
+    if (mnt->data != NULL) {
+        data = (u_char *) nxt_strdup(mnt->data);
+        if (nxt_slow_path(data == NULL)) {
+            return NXT_ERROR;
+        }
+
+        end = data - 1;
+
+        do {
+            p = end + 1;
+            end = nxt_strchr(p, '=');
+            if (end == NULL) {
+                break;
+            }
+
+            *end = '\0';
+
+            iov[iovlen].iov_base = (void *) p;
+            iov[iovlen].iov_len = (end - p) + 1;
+
+            iovlen++;
+
+            p = end + 1;
+
+            end = nxt_strchr(p, ',');
+            if (end != NULL) {
+                *end = '\0';
+            }
+
+            iov[iovlen].iov_base = (void *) p;
+            iov[iovlen].iov_len = nxt_strlen(p) + 1;
+
+            iovlen++;
+
+        } while (end != NULL && nxt_nitems(iov) > (iovlen + 2));
+    }
+
+    ret = NXT_OK;
+
+    if (nxt_slow_path(nmount(iov, iovlen, flags) < 0)) {
+        nxt_alert(task, "nmount(%p, %d, 0) %s", iov, iovlen, errmsg);
+        ret = NXT_ERROR;
+    }
+
+    if (data != NULL) {
+        free(data);
+    }
+
+    return ret;
+}
+
+#endif
+
+
+#if (NXT_HAVE_LINUX_UMOUNT2)
+
+void
+nxt_fs_unmount(const u_char *path)
+{
+    if (nxt_slow_path(umount2((const char *) path, MNT_DETACH) < 0)) {
+        nxt_thread_log_error(NXT_LOG_WARN, "umount2(%s, MNT_DETACH) %E",
+                             path, nxt_errno);
+    }
+}
+
+#elif (NXT_HAVE_UNMOUNT)
+
+void
+nxt_fs_unmount(const u_char *path)
+{
+    if (nxt_slow_path(unmount((const char *) path, MNT_FORCE) < 0)) {
+        nxt_thread_log_error(NXT_LOG_WARN, "unmount(%s) %E", path, nxt_errno);
+    }
+}
+
+#endif
diff --git a/src/nxt_fs_mount.h b/src/nxt_fs_mount.h
new file mode 100644
index 00000000..e0fe6eb2
--- /dev/null
+++ b/src/nxt_fs_mount.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) NGINX, Inc.
+ */
+
+#ifndef _NXT_FS_MOUNT_H_INCLUDED_
+#define _NXT_FS_MOUNT_H_INCLUDED_
+
+
+typedef enum nxt_fs_type_s     nxt_fs_type_t;
+typedef enum nxt_fs_flags_s    nxt_fs_flags_t;
+typedef struct nxt_fs_mount_s  nxt_fs_mount_t;
+
+
+enum nxt_fs_type_s {
+    NXT_FS_UNKNOWN = 0,
+    NXT_FS_BIND,
+    NXT_FS_TMP,
+    NXT_FS_PROC,
+    NXT_FS_LAST,
+};
+
+
+enum nxt_fs_flags_s {
+    NXT_FS_FLAGS_NOSUID   = 1 << 0,
+    NXT_FS_FLAGS_NOEXEC   = 1 << 1,
+    NXT_FS_FLAGS_NOTIME   = 1 << 2,
+    NXT_FS_FLAGS_NODEV    = 1 << 3,
+    NXT_FS_FLAGS_RDONLY   = 1 << 4,
+};
+
+
+struct nxt_fs_mount_s {
+    u_char          *src;
+    u_char          *dst;
+    nxt_fs_type_t   type;
+    u_char          *name;
+    nxt_fs_flags_t  flags;
+    u_char          *data;
+    nxt_uint_t      builtin;  /* 1-bit */
+    nxt_uint_t      deps;     /* 1-bit */
+};
+
+
+nxt_int_t nxt_fs_mount(nxt_task_t *task, nxt_fs_mount_t *mnt);
+void nxt_fs_unmount(const u_char *path);
+
+
+#endif  /* _NXT_FS_MOUNT_H_INCLUDED_ */
diff --git a/src/nxt_main.h b/src/nxt_main.h
index dca4b6dc..a51a1ce7 100644
--- a/src/nxt_main.h
+++ b/src/nxt_main.h
@@ -59,6 +59,7 @@ typedef uint16_t                     nxt_port_id_t;
 #include <nxt_process_type.h>
 #include <nxt_capability.h>
 #include <nxt_credential.h>
+#include <nxt_fs_mount.h>
 #include <nxt_fs.h>
 #include <nxt_process.h>
 #include <nxt_utf8.h>