gfapi: provide an api for setting statedump path

Currently for an application using glfsapi to use glusterfs, when a
statedump is taken, it uses /var/run/gluster dir to dump info.

There can be concerns as this directory may be owned by some other
user, and hence it may fail taking statedump. Such applications
should have an option to use different path.

This patch provides an API to do so.

Updates: bz#1689097
Change-Id: I8918e002bc823d83614c972b6c738baa04681b23
Signed-off-by: Amar Tumballi <amarts@redhat.com>

4 files changed, 98 insertions, 0 deletions

diff --git a/api/src/gfapi.aliases b/api/src/gfapi.aliases
index 09c0fd8f64..8fdf734458 100644
--- a/api/src/gfapi.aliases
+++ b/api/src/gfapi.aliases
@@ -195,3 +195,5 @@ _pub_glfs_zerofill_async _glfs_zerofill_async$GFAPI_6.0
 _pub_glfs_copy_file_range _glfs_copy_file_range$GFAPI_6.0
 _pub_glfs_fsetattr _glfs_fsetattr$GFAPI_6.0
 _pub_glfs_setattr _glfs_setattr$GFAPI_6.0
+
+_pub_glfs_set_statedump_path _glfs_set_statedump_path@GFAPI_future
diff --git a/api/src/gfapi.map b/api/src/gfapi.map
index b97a614c13..cf118e8ebe 100644
--- a/api/src/gfapi.map
+++ b/api/src/gfapi.map
@@ -271,3 +271,8 @@ GFAPI_PRIVATE_6.1 {
 	global:
 		glfs_setfspid;
 } GFAPI_6.0;
+
+GFAPI_future {
+	global:
+		glfs_set_statedump_path;
+} GFAPI_PRIVATE_6.1;
diff --git a/api/src/glfs.c b/api/src/glfs.c
index f26affbd47..b0db866441 100644
--- a/api/src/glfs.c
+++ b/api/src/glfs.c
@@ -1211,6 +1211,7 @@ glusterfs_ctx_destroy(glusterfs_ctx_t *ctx)
         glusterfs_graph_destroy_residual(trav_graph);
     }
 
+    GF_FREE(ctx->statedump_path);
     FREE(ctx);
 
     return ret;
@@ -1737,3 +1738,65 @@ invalid_fs:
 }
 
 GFAPI_SYMVER_PUBLIC_DEFAULT(glfs_upcall_unregister, 3.13.0);
+
+int
+pub_glfs_set_statedump_path(struct glfs *fs, const char *path)
+{
+    struct stat st;
+    int ret;
+    DECLARE_OLD_THIS;
+    __GLFS_ENTRY_VALIDATE_FS(fs, invalid_fs);
+
+    if (!path) {
+        gf_log("glfs", GF_LOG_ERROR, "path is NULL");
+        errno = EINVAL;
+        goto err;
+    }
+
+    /* If path is not present OR, if it is directory AND has enough permission
+     * to create files, then proceed */
+    ret = sys_stat(path, &st);
+    if (ret && errno != ENOENT) {
+        gf_log("glfs", GF_LOG_ERROR, "%s: not a valid path (%s)", path,
+               strerror(errno));
+        errno = EINVAL;
+        goto err;
+    }
+
+    if (!ret) {
+        /* file is present, now check other things */
+        if (!S_ISDIR(st.st_mode)) {
+            gf_log("glfs", GF_LOG_ERROR, "%s: path is not directory", path);
+            errno = EINVAL;
+            goto err;
+        }
+        if (sys_access(path, W_OK | X_OK) < 0) {
+            gf_log("glfs", GF_LOG_ERROR,
+                   "%s: path doesn't have write permission", path);
+            errno = EPERM;
+            goto err;
+        }
+    }
+
+    /* If set, it needs to be freed, so we don't have leak */
+    GF_FREE(fs->ctx->statedump_path);
+
+    fs->ctx->statedump_path = gf_strdup(path);
+    if (!fs->ctx->statedump_path) {
+        gf_log("glfs", GF_LOG_ERROR,
+               "%s: failed to set statedump path, no memory", path);
+        errno = ENOMEM;
+        goto err;
+    }
+
+    __GLFS_EXIT_FS;
+
+    return 0;
+err:
+    __GLFS_EXIT_FS;
+
+invalid_fs:
+    return -1;
+}
+
+GFAPI_SYMVER_PUBLIC_DEFAULT(glfs_set_statedump_path, future);
diff --git a/api/src/glfs.h b/api/src/glfs.h
index 671478206b..a6c12e128d 100644
--- a/api/src/glfs.h
+++ b/api/src/glfs.h
@@ -1453,5 +1453,33 @@ int
 glfs_setattr(struct glfs *fs, const char *path, struct glfs_stat *stat,
              int follow) __THROW GFAPI_PUBLIC(glfs_setattr, 6.0);
 
+/*
+  SYNOPSIS
+
+  glfs_set_statedump_path: Function to set statedump path.
+
+  DESCRIPTION
+
+  This function is used to set statedump directory
+
+  PARAMETERS
+
+  @fs: The 'virtual mount' object to be configured with the volume
+       specification file.
+
+  @path: statedump path. Should be a directory. But the API won't fail if the
+  directory doesn't exist yet, as one may create it later.
+
+  RETURN VALUES
+
+   0 : Success.
+  -1 : Failure. @errno will be set with the type of failure.
+
+ */
+
+int
+glfs_set_statedump_path(struct glfs *fs, const char *path) __THROW
+    GFAPI_PUBLIC(glfs_set_statedump_path, future);
+
 __END_DECLS
 #endif /* !_GLFS_H */