Commit Graph

6 Commits

Author SHA1 Message Date
David Crawshaw 03da2690c9 cmd/link, runtime, plugin: versioning
In plugins and every program that opens a plugin, include a hash of
every imported package.

There are two versions of each hash: one local and one exported.
As the program starts and plugins are loaded, the first exported
symbol for each package becomes the canonical version.

Any subsequent plugin's local package hash symbol has to match the
canonical version.

Fixes #17832

Change-Id: I4e62c8e1729d322e14b1673bada40fa7a74ea8bc
Reviewed-on: https://go-review.googlesource.com/33161
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-15 16:14:27 +00:00
David Crawshaw 54ec7b072e runtime: access modules via a slice
The introduction of -buildmode=plugin means modules can be added to a
Go program while it is running. This means there exists some time
while the program is running with the module is on the moduledata
linked list, but it has not been initialized to the satisfaction of
other parts of the runtime. Notably, the GC.

This CL adds a new way of access modules, an activeModules function.
It returns a slice of modules that is built in the background and
atomically swapped in. The parts of the runtime that need to wait on
module initialization can use this slice instead of the linked list.

Fixes #17455

Change-Id: I04790fd07e40c7295beb47cea202eb439206d33d
Reviewed-on: https://go-review.googlesource.com/32357
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-01 16:04:12 +00:00
David Crawshaw 9da7058466 cmd/link, plugin: use full plugin path for symbols
Plumb the import path of a plugin package through to the linker, and
use it as the prefix on the exported symbol names.

Before this we used the basename of the plugin file as the prefix,
which could conflict and result in multiple loaded plugins sharing
symbols that are distinct.

Fixes #17155
Fixes #17579

Change-Id: I7ce966ca82d04e8507c0bcb8ea4ad946809b1ef5
Reviewed-on: https://go-review.googlesource.com/32355
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-10-31 04:48:42 +00:00
David Crawshaw b4c9829c22 runtime: check plugin-loaded moduledata addresses
Inspired by difficulties with plugin support on darwin.

Change-Id: I2cef8410837946454e75d00e94e46791f03f2267
Reviewed-on: https://go-review.googlesource.com/29391
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-23 02:16:17 +00:00
David Crawshaw 0cbb12f0bb plugin: new package for loading plugins
Includes a linux implementation.

Change-Id: Iacc2ed7da760ae9deebc928adf2b334b043b07ec
Reviewed-on: https://go-review.googlesource.com/27823
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-16 17:54:40 +00:00
David Crawshaw eced6754c2 cmd/link: -buildmode=plugin support for linux
This CL contains several linker changes to support creating plugins.

It collects the exported plugin symbols provided by the compiler and
includes them in the moduledata.

It treats a binary as being dynamically linked if it imports the plugin
package. This lets the dynamic linker de-duplicate symbols.

Change-Id: I099b6f38dda26306eba5c41dbe7862f5a5918d95
Reviewed-on: https://go-review.googlesource.com/27820
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-16 14:49:13 +00:00