Add capability to add symlink to task sandbox namespace.

taskvine/src/manager/Makefile

@@ -15,6 +15,7 @@ SOURCES = \
 	vine_task.c \
 	vine_file.c \
 	vine_mount.c \
+	vine_symlink.c \
 	vine_txn_log.c \
 	vine_taskgraph_log.c \
 	vine_cached_name.c \

taskvine/src/manager/taskvine.h

@@ -446,6 +446,15 @@ feature.
 */
 void vine_task_add_feature(struct vine_task *t, const char *name);
 
+/** Add a symbolic link to the sandbox namespace of the task.
+This can be used to access a file within a shared filesystem,
+without causing the file to be transferred using the taskvine caching infrastructure.
+@param t A task object;
+@param name The name of the symlink; must be a relative path in the task sandbox.
+@param target The target of the symlink; must be an absolute path to an outside filesystem.
+*/
+void vine_task_add_symlink(struct vine_task *t, const char *name, const char *target);
+
 /** Specify the priority of this task relative to others in the manager.
 Tasks with a higher priority value run first. If no priority is given, a task is placed at the end of the ready list,
 regardless of the priority.

taskvine/src/manager/vine_manager_put.c

@@ -11,6 +11,7 @@ See the file COPYING for details.
 #include "vine_file_replica_table.h"
 #include "vine_mount.h"
 #include "vine_protocol.h"
+#include "vine_symlink.h"
 #include "vine_task.h"
 #include "vine_txn_log.h"
 #include "vine_worker_info.h"
@@ -560,6 +561,18 @@ vine_result_code_t vine_manager_put_task(
 		}
 	}
 
+	if (t->symlink_list) {
+		struct vine_symlink *s;
+		LIST_ITERATE(t->symlink_list, s)
+		{
+			char name_encoded[PATH_MAX];
+			char target_encoded[PATH_MAX];
+			url_encode(s->name, name_encoded, PATH_MAX);
+			url_encode(s->target, target_encoded, PATH_MAX);
+			vine_manager_send(q, w, "symlink %s %s\n", name_encoded, target_encoded );
+		}
+	}
+
 	// vine_manager_send returns the number of bytes sent, or a number less than
 	// zero to indicate errors. We are lazy here, we only check the last
 	// message we sent to the worker (other messages may have failed above).

taskvine/src/manager/vine_task.c

@@ -9,6 +9,7 @@ See the file COPYING for details.
 #include "vine_file.h"
 #include "vine_manager.h"
 #include "vine_mount.h"
+#include "vine_symlink.h"
 #include "vine_worker_info.h"
 
 #include "debug.h"
@@ -51,6 +52,7 @@ struct vine_task *vine_task_create(const char *command_line)
 
 	t->input_mounts = list_create();
 	t->output_mounts = list_create();
+	t->symlink_list = list_create();
 	t->env_list = list_create();
 	t->feature_list = list_create();
 
@@ -177,6 +179,17 @@ static void vine_task_mount_list_copy(struct list *destination, struct list *lis
 	}
 }
 
+static void vine_task_symlink_list_copy(struct list *destination, struct list *list)
+{
+	struct vine_symlink *old_symlink, *new_symlink;
+
+	LIST_ITERATE(list, old_symlink)
+	{
+		new_symlink = vine_symlink_copy(old_symlink);
+		list_push_tail(destination, new_symlink);
+	}
+}
+
 static void vine_task_string_list_copy(struct list *destination, struct list *string_list)
 {
 	char *var;
@@ -230,6 +243,7 @@ struct vine_task *vine_task_copy(const struct vine_task *task)
 
 	vine_task_mount_list_copy(new->input_mounts, task->input_mounts);
 	vine_task_mount_list_copy(new->output_mounts, task->output_mounts);
+	vine_task_symlink_list_copy(new->symlink_list, task->symlink_list);
 	vine_task_string_list_copy(new->env_list, task->env_list);
 	vine_task_string_list_copy(new->feature_list, task->feature_list);
 	new->function_slots_requested = task->function_slots_requested;
@@ -636,6 +650,11 @@ int vine_task_add_environment(struct vine_task *t, struct vine_file *f)
 	return vine_task_add_execution_context(t, f);
 }
 
+void vine_task_add_symlink(struct vine_task *t, const char *name, const char *target)
+{
+	list_push_tail(t->symlink_list,vine_symlink_create(name,target));
+}
+
 int vine_task_add_execution_context(struct vine_task *t, struct vine_file *context_file)
 {
 	if (!context_file) {
@@ -754,6 +773,9 @@ void vine_task_delete(struct vine_task *t)
 	list_clear(t->output_mounts, (void *)vine_mount_delete);
 	list_delete(t->output_mounts);
 
+	list_clear(t->symlink_list, (void*)vine_symlink_delete);
+	list_delete(t->symlink_list);
+
 	list_clear(t->env_list, (void *)free);
 	list_delete(t->env_list);
 

taskvine/src/manager/vine_task.h

@@ -59,8 +59,9 @@ struct vine_task {
 	int   function_slots_requested; /**< If this is a LibraryTask, the number of function slots requested by the user. -1 causes the number of slots to match the number of cores. */
         vine_task_func_exec_mode_t func_exec_mode;    /**< If this a LibraryTask, the execution mode of its functions. */
 
-	struct list *input_mounts;    /**< The mounted files expected as inputs. */
-	struct list *output_mounts;   /**< The mounted files expected as outputs. */
+	struct list *input_mounts;   /**< The mounted files expected as inputs. */
+	struct list *output_mounts;  /**< The mounted files expected as outputs. */
+	struct list *symlink_list;   /**< Additional symlinks to add to the sandbox namespace. */
 	struct list *env_list;       /**< Environment variables applied to the task. */
 	struct list *feature_list;   /**< User-defined features this task requires. (See vine_worker's --feature option.) */
 

taskvine/src/worker/vine_sandbox.c

@@ -9,6 +9,7 @@ See the file COPYING for details.
 #include "vine_cache_file.h"
 #include "vine_file.h"
 #include "vine_mount.h"
+#include "vine_symlink.h"
 #include "vine_task.h"
 #include "vine_worker.h"
 
@@ -134,6 +135,7 @@ int vine_sandbox_stagein(struct vine_process *p, struct vine_cache *cache)
 	int result = 1;
 
 	struct vine_mount *m;
+	struct vine_symlink *s;
 
 	/* For each input mount, stage it into the sandbox. */
 
@@ -144,6 +146,17 @@ int vine_sandbox_stagein(struct vine_process *p, struct vine_cache *cache)
 			break;
 	}
 
+	/* For each requested symlink, create it in the sandbox */
+
+	LIST_ITERATE(t->symlink_list, s)
+	{
+		result = symlink(s->target,s->name);
+		if(result!=0) {
+			debug(D_VINE,"unable to symlink %s -> %s: %s",s->name,s->target,strerror(errno));
+			break;
+		}
+	}
+
 	/* If any of the output mounts have the MKDIR flag, then create those empty dirs. */
 
 	LIST_ITERATE(t->output_mounts, m)

taskvine/src/worker/vine_worker.c

@@ -834,6 +834,8 @@ static struct vine_task *do_task_body(struct link *manager, int task_id, time_t
 	char localname[VINE_LINE_MAX];
 	char taskname[VINE_LINE_MAX];
 	char taskname_encoded[VINE_LINE_MAX];
+	char target[VINE_LINE_MAX];
+	char target_encoded[VINE_LINE_MAX];
 	char library_name[VINE_LINE_MAX];
 	char category[VINE_LINE_MAX];
 	int flags, length;
@@ -873,6 +875,10 @@ static struct vine_task *do_task_body(struct link *manager, int task_id, time_t
 			url_decode(taskname_encoded, taskname, VINE_LINE_MAX);
 			vine_hack_do_not_compute_cached_name = 1;
 			vine_task_add_output_file(task, localname, taskname, flags);
+		} else if (sscanf(line, "symlink %s %s", taskname_encoded, target_encoded)==2) {
+			url_decode(taskname_encoded, taskname, VINE_LINE_MAX);
+			url_decode(target_encoded, target, VINE_LINE_MAX);
+			vine_task_add_symlink(task,taskname,target);
 		} else if (sscanf(line, "cores %" PRId64, &n)) {
 			vine_task_set_cores(task, n);
 		} else if (sscanf(line, "memory %" PRId64, &n)) {