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78 Commits

Author SHA1 Message Date
Dmitri Shuralyov ea96074191 [release-branch.go1.22] os/exec: only use cachedLookExtensions if Cmd.Path is unmodified
Caching the invocation of lookExtensions on an absolute path in Command
and reusing the cached result in Start is only viable if Cmd.Path isn't
set to a different value after Command returns.

For #66586.
For #68314.
Fixes #68331.

Change-Id: I57007850aca2011b11344180c00faded737617b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/596875
Reviewed-by: qiu laidongfeng2 <2645477756@qq.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
(cherry picked from commit d0146bd85b)
Reviewed-on: https://go-review.googlesource.com/c/go/+/596976
2024-07-10 19:24:54 +00:00
qiulaidongfeng dfe4dbf8c0 [release-branch.go1.22] os/exec: on Windows look for extensions in Run if not already done
CL 512155 fixed #36768, but introduced #62596.
CL 527820 fixed #62596, but meant that the code failed to look up
file extensions on Windows for a relative path.
This CL fixes that problem by recording whether it has already
looked up file extensions.
This does mean that if Path is set manually then we do not update
it with file extensions, as doing that would be racy.

For #66586
Fixes #66598

Change-Id: I9a0305d1e466c5e07bfbe442566ea12f5255a96e
GitHub-Last-Rev: dc3169f235
GitHub-Pull-Request: golang/go#67035
Reviewed-on: https://go-review.googlesource.com/c/go/+/581695
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Reviewed-by: Ian Lance Taylor <iant@google.com>
(cherry picked from commit 5532427c4b)
Reviewed-on: https://go-review.googlesource.com/c/go/+/594495
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>
2024-06-24 20:39:41 +00:00
Bryan C. Mills f7f266c885 os/exec: avoid calling LookPath in cmd.Start for resolved paths
This reapplies CL 512155, which was previously reverted in CL 527337.
The race that prompted the revert should be fixed by CL 527820,
which will be submitted before this one.

For #36768.
Updates #62596.

Change-Id: I3c3cd92470254072901b6ef91c0ac52c8071e0a2
Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-race,gotip-windows-amd64-race,gotip-windows-amd64-longtest
Reviewed-on: https://go-review.googlesource.com/c/go/+/528038
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2023-09-13 19:38:12 +00:00
Bryan C. Mills 36facaa1f9 os/exec: avoid writing to Cmd.Path in Cmd.Start on Windows
Fixes #62596.

Change-Id: I9003318ac1c4e3036f32383e62e9ba08c383d5c2
Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-race,gotip-windows-amd64-race,gotip-windows-amd64-longtest
Reviewed-on: https://go-review.googlesource.com/c/go/+/527820
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2023-09-13 19:25:41 +00:00
Ian Lance Taylor 8221f90f13 Revert "os/exec: avoid calling LookPath in cmd.Start for resolved paths"
This reverts CL 512155.

Reason for revert: CL 512155 introduced a race in that it caused
cmd.Start to set cmd.Path. Previously it was fine if code looked
at cmd.Path in one goroutine while calling cmd.Start in a different
goroutine.

A test case for this race is in CL 527495.

Change-Id: Ic18fdadf6763727f8ea748280d5f0e601b9bf374
Reviewed-on: https://go-review.googlesource.com/c/go/+/527337
Auto-Submit: Ian Lance Taylor <iant@golang.org>
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Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2023-09-12 00:57:26 +00:00
apocelipes 29253f4d51 os/exec: Use the built-in function min instead of minInt
The built-in function `min` has been implemented and can now be used to replace some manually written `minType` helper functions.

Change-Id: Ie8ffc7881c8652ece752751214f1242bf76a6e7e
GitHub-Last-Rev: 5db344f131
GitHub-Pull-Request: golang/go#60866
Reviewed-on: https://go-review.googlesource.com/c/go/+/504315
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Reviewed-by: qiulaidongfeng <2645477756@qq.com>
2023-08-01 14:29:09 +00:00
qiulaidongfeng 616193510f os/exec: avoid calling LookPath in cmd.Start for resolved paths
Follow up on CL 511458, see https://go-review.googlesource.com/c/go/+/511458/2..4/src/cmd/go/main.go#b270 .

For #36768.

Change-Id: Icc2a4dbb1219b1d69dd10a900478957b0e975847

Change-Id: Icc2a4dbb1219b1d69dd10a900478957b0e975847
GitHub-Last-Rev: bac7e66496
GitHub-Pull-Request: golang/go#61517
Reviewed-on: https://go-review.googlesource.com/c/go/+/512155
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2023-07-26 11:13:35 +00:00
Russ Cox 14ab998f95 cmd/go: add check for unknown godebug setting
A //go:debug line mentioning an unknown or retired setting
should be diagnosed as making the program invalid. Do that.
We agreed on this in the proposal but I forgot to implement it.

Change-Id: Ie69072a1682d4eeb6866c02adbbb426f608567c4
Reviewed-on: https://go-review.googlesource.com/c/go/+/476280
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2023-04-18 13:19:19 +00:00
Russ Cox ea4631cc0c internal/godebug: define more efficient API
We have been expanding our use of GODEBUG for compatibility,
and the current implementation forces a tradeoff between
freshness and efficiency. It parses the environment variable
in full each time it is called, which is expensive. But if clients
cache the result, they won't respond to run-time GODEBUG
changes, as happened with x509sha1 (#56436).

This CL changes the GODEBUG API to provide efficient,
up-to-date results. Instead of a single Get function,
New returns a *godebug.Setting that itself has a Get method.
Clients can save the result of New, which is no more expensive
than errors.New, in a global variable, and then call that
variable's Get method to get the value. Get costs only two
atomic loads in the case where the variable hasn't changed
since the last call.

Unfortunately, these changes do require importing sync
from godebug, which will mean that sync itself will never
be able to use a GODEBUG setting. That doesn't seem like
such a hardship. If it was really necessary, the runtime could
pass a setting to package sync itself at startup, with the
caveat that that setting, like the ones used by runtime itself,
would not respond to run-time GODEBUG changes.

Change-Id: I99a3acfa24fb2a692610af26a5d14bbc62c966ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/449504
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2022-11-14 15:19:57 +00:00
Matthew Dempsky bc2dc23846 os/exec: allow NUL in environment variables on Plan 9
Plan 9 uses NUL as os.PathListSeparator, so it's almost always going
to appear in the environment variable list. Exempt GOOS=plan9 from the
check for NUL in environment variables.

For #56284.
Fixes #56544.

Change-Id: I23df233cdf20c0a9a606fd9253e15a9b5482575a
Reviewed-on: https://go-review.googlesource.com/c/go/+/447715
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2022-11-04 01:23:16 +00:00
Damien Neil 61ae0a37a8 syscall, os/exec: reject environment variables containing NULs
Check for and reject environment variables containing NULs.

The conventions for passing environment variables to subprocesses
cause most or all systems to interpret a NUL as a separator. The
syscall package rejects environment variables containing a NUL
on most systems, but erroniously did not do so on Windows. This
causes an environment variable such as "FOO=a\x00BAR=b" to be
interpreted as "FOO=a", "BAR=b".

Check for and reject NULs in environment variables passed to
syscall.StartProcess on Windows.

Add a redundant check to os/exec as extra insurance.

Fixes #56284
Fixes CVE-2022-41716

Change-Id: I2950e2b0cb14ebd26e5629be1521858f66a7d4ae
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1609434
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2022-11-01 16:40:37 +00:00
Bryan C. Mills 55eaae452c os/exec: add the Cancel and WaitDelay fields
Fixes #50436.

Change-Id: I9dff8caa317a04b7b2b605f810b8f12ef8ca485d
Reviewed-on: https://go-review.googlesource.com/c/go/+/401835
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2022-10-25 03:34:36 +00:00
Bryan C. Mills 0f64a49460 os/exec: remove protection against a duplicate Close on StdinPipe
As of CL 438347, multiple concurrents calls to Close should be safe.

This removes some indirection and may also make some programs that use
type-assertions marginally more efficient. For example, if a program
calls (*exec.Cmd).StdinPipe to obtain a pipe and then sets that as the
Stdout of another command, that program will now allow the second
command to inherit the file descriptor directly instead of copying
everything through a goroutine.

This will also cause calls to Close after the first to return an error
wrapping os.ErrClosed instead of nil. However, it seems unlikely that
programs will depend on that error behavior: if a program is calling
Write in a loop followed by Close, then if a racing Close occurs it is
likely that the Write would have already reported an error. (The only
programs likely to notice a change are those that call Close — without
Write! — after a call to Wait.)

Updates #56043.
Updates #9307.
Updates #6270.

Change-Id: Iec734b23acefcc7e7ad0c8bc720085bc45988efb
Reviewed-on: https://go-review.googlesource.com/c/go/+/439195
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2022-10-11 14:31:32 +00:00
hopehook fdea8e2170 os/exec: document ProcessState available after a call to Wait or Run
Wait or Run will populate its ProcessState when the command completes.

Fixes #56002.

Change-Id: I21547431f5d2d3e0fc0734fd1705421a0ac4209c
Reviewed-on: https://go-review.googlesource.com/c/go/+/437996
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2022-10-07 02:16:49 +00:00
Bryan C. Mills 0fec65d281 os/exec: add a GODEBUG setting to diagnose leaked processes
Updates #52580.
For #50436.

Change-Id: I669f13863f1f85d576c3c94500b118e6989000eb
Reviewed-on: https://go-review.googlesource.com/c/go/+/436655
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2022-10-04 23:19:13 +00:00
Bryan Mills 3380ee2520 Revert "os/exec: make StdoutPipe and StderrPipe safe to Close concurrently"
This reverts CL 437176.

Reason for revert: broke programs that plumb StdoutPipe from one command to Stdin on another and then call Wait on the former.

os/exec itself uses a type-assertion to *os.File to determine whether to copy stdin using a goroutine or just pass a file descriptor. An early Wait using a *os.File is benign (because closing the pipe doesn't close the child's inherited file descriptor), but an early Wait using a non-*os.File is not.

Updates #50436.

Change-Id: I4a2993e290982834f91696d890dfe77364c0cc50
Reviewed-on: https://go-review.googlesource.com/c/go/+/438695
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2022-10-04 21:17:23 +00:00
Bryan C. Mills 9a029a6915 os/exec: make StdoutPipe and StderrPipe safe to Close concurrently
For #50436, I want to be able to close the pipes returned by
StdoutPipe and StderrPipe after the Context has been canceled
and the WaitDelay has subsequently expired.

However, the fact that the exec.onceCloser wrapper for StdinPipe
(added in CL 13329043) was retained in CL 65490 suggests to me that
(*os.File).Close is still not safe to call concurrently.

This may cause type assertions of these ReadClosers to *os.File that
once succeeded to no longer do so. However, the StdoutPipe and
StderrPipe methods return interfaces, not concrete *os.Files, so
callers already should not have been relying on that implementation
detail — and as far as I can tell the closeOnce wrapper does not mask
any (*os.File) methods, so assertions to any interface type that
previously succeeded will continue to do so.

This change is logically part of CL 401835, but since it may expose
fragile type-assertions in callers I want to keep it separate for
clearer bisection of any new test failures.

For #50436.

Change-Id: I58de1d48fb6fd788502f13657d8d4484516271cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/437176
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2022-10-01 00:21:25 +00:00
Bryan C. Mills c9a62b7e71 os/exec: recombine goroutinePipes and userPipes
This change undoes CL 401894, because on further consideration
it turns out not to be needed.

This also makes (*Cmd).closeDescriptors a free function, since it does
not actually use the receiver in any way and is not needed to satisfy
any interfaces.

For #50436.

Change-Id: I7915265b0e6398ed5a34fae0c12873ab08a14194
Reviewed-on: https://go-review.googlesource.com/c/go/+/437175
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2022-10-01 00:12:32 +00:00
Bryan C. Mills 223a563f58 os/exec: refactor goroutine error reporting
Use a separate channel to report the final error of the copying
goroutines, receiving a value only when all of the copying goroutines
have completed. In a followup change (CL 401835), that will allow
waiters to select on goroutine completion alongside other events (such
as Context cancellation).

Also mildly refactor the watchCtx helper method so that its structure
better matches what will be needed to implement WaitDelay.

For #50436.

Change-Id: I54b3997fb6931d204814d8382f0a388a67b520f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/435995
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2022-09-29 02:34:30 +00:00
Bryan C. Mills 4d6ca68a85 os/exec: do not close pipes on a double-Start error
This fixes a bug introduced in CL 401834 in which calling Start twice
with pipes attached to a command would spuriously close those pipes
when returning the error from the second Start call.

For #50436.

Change-Id: I3563cc99c0a0987752190fef95da3e9927a76fda
Reviewed-on: https://go-review.googlesource.com/c/go/+/436095
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2022-09-29 02:28:26 +00:00
Bryan C. Mills bd8a5b00fc os/exec: split parent I/O pipes by whether they are pumped by user code or internal goroutines
The pipes pumped by goroutines can be closed as soon as their
respective goroutines are done.

The pipes pumped by user code, however, are documented to be closed in
Wait. When we add the WaitDelay field, it isn't obvious that we should
terminate the user-pumped pipes when the WaitDelay expires, since Wait
itself isn't going to wait for those user-controlled goroutines to
complete.

(It's a bit more complicated than that because the documentation
currently states that Wait must not be called while the pipes are
being read — but it isn't obvious to me that that advice is entirely
correct.)

For #50436.

Change-Id: I97909c91d2097fb75138a360747168c08609696d
Reviewed-on: https://go-review.googlesource.com/c/go/+/401894
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2022-09-26 17:26:59 +00:00
Bryan C. Mills b8d4a14a66 os/exec: clean up pipe-closing logic
Change the childFiles field to a local variable, since it was
populated during Start and (as far as I can determine) has no purpose
after Start returns.

Rename closeAfterStart and closeAfterWait to childIOFiles and
parentIOPipes respectively. That makes their contents clearer, and also
helps to clarify what should happen on error (when, for example, Wait
shouldn't be called at all).

Use a deferred call instead of individual calls to close child (and,
if necessary, pipe) FDs after Start. That helps to clarify the
invariants around when they are closed, and also makes the function a
bit more robust for future refactoring.

Also nil out the slices containing the file closers so that they can
be collected earlier.

This CL is intended as a pure refactor in preparation for #50436.

Change-Id: I05d13fa91d539b95b84b2ba923c1733f9a6203e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/401834
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2022-09-26 17:26:56 +00:00
Russ Cox 027855e8d8 os/exec: add GODEBUG setting to opt out of ErrDot changes
The changes are likely to break users, and we need
to make it easy to unbreak without code changes.

For #43724.
Fixes #53962.

Change-Id: I105c5d6c801d354467e0cefd268189c18846858e
Reviewed-on: https://go-review.googlesource.com/c/go/+/419794
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2022-07-28 19:12:40 +00:00
Ian Lance Taylor 53a4152d47 os/exec: clarify that Wait must be called
Fixes #52580

Change-Id: Ib2dd8a793b9c6fcb083abb3f7c346f6279adefc9
Reviewed-on: https://go-review.googlesource.com/c/go/+/414056
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2022-07-06 16:51:00 +00:00
Russ Cox 960ffa98ce os/exec: return clear error for missing cmd.Path
Following up on CL 403694, there is a bit of confusion about
when Path is and isn't set, along with now the exported Err field.
Catch the case where Path and Err (and lookPathErr) are all unset
and give a helpful error.

Fixes #52574
Followup after #43724.

Change-Id: I03205172aef3801c3194f5098bdb93290c02b1b6
Reviewed-on: https://go-review.googlesource.com/c/go/+/403759
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
2022-05-10 17:29:08 +00:00
Bryan C. Mills 4e79f06dac os/exec: refactor goroutine communication in Wait
This provides clearer synchronization invariants: if it occurs at all,
the call to c.Process.Kill always occurs before Wait returns. It also
allows any unexpected errors from the goroutine to be propagated back
to Wait.

For #50436.

Change-Id: I7ddadc73e6e67399596e35393f5845646f6111ab
Reviewed-on: https://go-review.googlesource.com/c/go/+/401896
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2022-05-06 22:04:35 +00:00
Bryan C. Mills 61a585a32c os/exec: in Command, update cmd.Path even if LookPath returns an error
Fixes #52666.
Updates #43724.
Updates #43947.

Change-Id: I72cb585036b7e93cd7adbff318b400586ea97bd5
Reviewed-on: https://go-review.googlesource.com/c/go/+/403694
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2022-05-03 16:29:56 +00:00
Russ Cox 349cc83389 os/exec: return error when PATH lookup would use current directory
CL 381374 was reverted because x/sys/execabs broke.

This CL reapplies CL 381374, but adding a lookPathErr error
field back, for execabs to manipulate with reflect.
That field will just be a bit of scar tissue in this package forever,
to keep old code working with new toolchains.

CL 403256 fixes x/sys/execabs's test to be ready for the change.
Older versions of x/sys/execabs will keep working
(that is, will keep rejecting what they should reject),
but they will return a slightly different error from LookPath
without that CL, and the test fails because of the different
error text.

For #43724.

This reverts commit f2b674756b.

Change-Id: Iee55f8cd9939e1bd31e5cbdada50681cdc505117
Reviewed-on: https://go-review.googlesource.com/c/go/+/403274
Auto-Submit: Russ Cox <rsc@golang.org>
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2022-05-02 14:54:05 +00:00
Bryan Mills f2b674756b Revert "os/exec: return error when PATH lookup would use current directory"
This reverts CL 381374.

Reason for revert: broke tests for x/sys/execabs.

Updates #43724.
Updates #43947.

Change-Id: I9eb3adb5728dead66dbd20f6afe1e7a77e2a26f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/403058
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
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2022-04-29 23:04:17 +00:00
Russ Cox 3ce203db80 os/exec: return error when PATH lookup would use current directory
Following discussion on #43724, change os/exec to take the
approach of golang.org/x/sys/execabs, refusing to respect
path entries mentioning relative paths by default.

Code that insists on being able to find executables in relative
directories in the path will need to add a couple lines to override the error.

See the updated package docs in exec.go for more details.

Fixes #43724.
Fixes #43947.

Change-Id: I73c1214f322b60b4167a23e956e933d50470fe13
Reviewed-on: https://go-review.googlesource.com/c/go/+/381374
Reviewed-by: Bryan Mills <bcmills@google.com>
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2022-04-29 20:16:31 +00:00
Bryan C. Mills ad5eaa8c4c os/exec: make skipStdinCopyError a function instead of a variable
This makes clearer that skipStdinCopyError is always defined and never
overridden in tests.

Secondarily, it may also help reduce init-time work and allow the
linker and/or inliner to better optimize this package.

(Noticed while prototyping #50436.)

Change-Id: I4f3c1bc146384a98136a4039f82165ed106c14b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/401897
Run-TryBot: Bryan Mills <bcmills@google.com>
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Reviewed-by: Ian Lance Taylor <iant@google.com>
2022-04-26 13:47:05 +00:00
Bryan C. Mills b34838913d os/exec: set PWD implicitly if Dir is non-empty and Env is nil
Fixes #50599.

Change-Id: I4e5dbb3972cdf21ede049567bfb98f2c992c5849
Reviewed-on: https://go-review.googlesource.com/c/go/+/401340
Run-TryBot: Bryan Mills <bcmills@google.com>
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Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2022-04-21 17:37:05 +00:00
Bryan C. Mills aa24255541 os/exec: preserve original order of entries in dedupEnv
Once #50599 is implemented, the entries will be observable via the
Environ method. I find it confusing for later entries in the list to
jump arbitrarily far forward based on entries for the same key that no
longer exist.

This also fixes the deduplication logic for the degenerate Windows
keys observed in #49886, which were previously deduplicated as empty
keys.

(It does not do anything about the even-more-degenerate keys observed
in #52436.)

For #50599.

Change-Id: Ia7cd2200ec34ccc4b9d18631cb513194dc420c25
Reviewed-on: https://go-review.googlesource.com/c/go/+/401339
Reviewed-by: Ian Lance Taylor <iant@google.com>
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2022-04-21 14:26:18 +00:00
Russ Cox 2580d0e08d all: gofmt -w -r 'interface{} -> any' src
And then revert the bootstrap cmd directories and certain testdata.
And adjust tests as needed.

Not reverting the changes in std that are bootstrapped,
because some of those changes would appear in API docs,
and we want to use any consistently.
Instead, rewrite 'any' to 'interface{}' in cmd/dist for those directories
when preparing the bootstrap copy.

A few files changed as a result of running gofmt -w
not because of interface{} -> any but because they
hadn't been updated for the new //go:build lines.

Fixes #49884.

Change-Id: Ie8045cba995f65bd79c694ec77a1b3d1fe01bb09
Reviewed-on: https://go-review.googlesource.com/c/go/+/368254
Trust: Russ Cox <rsc@golang.org>
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Reviewed-by: Robert Griesemer <gri@golang.org>
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2021-12-13 18:45:54 +00:00
Russ Cox 4d8db00641 all: use bytes.Cut, strings.Cut
Many uses of Index/IndexByte/IndexRune/Split/SplitN
can be written more clearly using the new Cut functions.
Do that. Also rewrite to other functions if that's clearer.

For #46336.

Change-Id: I68d024716ace41a57a8bf74455c62279bde0f448
Reviewed-on: https://go-review.googlesource.com/c/go/+/351711
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2021-10-06 15:53:04 +00:00
Liam 'Auzzie' Haworth e0c3ded337 os/exec: use environment variables for user token when present
Builds upon the changes from #32000 which supported sourcing environment
variables for a new process from the environment of a Windows user token
when supplied.

But due to the logic of os/exec, the Env field of a process was
always non-nil when it reached that change.

This change moves the logic up to os/exec, specifically when
os.ProcAttr is being built for the os.StartProcess call, this
ensures that if a user token has been supplied and no Env slice has
been provided on the command it will be sourced from the user's
environment.

If no token is provided, or the program is compiled for any other
platform than Windows, the default environment will be sourced from
syscall.Environ().

Fixes #35314

Change-Id: I4c1722e90b91945eb6980d5c5928183269b50487
GitHub-Last-Rev: 32216b7291
GitHub-Pull-Request: golang/go#37402
Reviewed-on: https://go-review.googlesource.com/c/go/+/220587
Run-TryBot: Ian Lance Taylor <iant@golang.org>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-02-25 02:05:29 +00:00
Fazlul Shahriar a3dc6da6d6 os/exec: ignore hungup error while copying stdin on Plan 9
Fixes #35753

Change-Id: I38674c59c601785eb25b778dc25efdb92231dd9b
Reviewed-on: https://go-review.googlesource.com/c/go/+/208223
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-12-15 15:34:17 +00:00
Günther Noack a18608a044 os/exec: document that cmd.Start() sets the Process field
Change-Id: I4f41b680741e9bd2a4e8c094ecf3ce6226e48d12
GitHub-Last-Rev: 8f58bc6c43
GitHub-Pull-Request: golang/go#35934
Reviewed-on: https://go-review.googlesource.com/c/go/+/209558
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-12-02 20:12:54 +00:00
Josh Bleecher Snyder a7042249ab os/exec: simplify doc wording for cmd.StdoutPipe and cmd.StderrPipe
The existing text was hard to parse.
Shorten the sentences and simplify the text.

Change-Id: Ic16f486925090ea303c04e70969e5a4b27a60896
Reviewed-on: https://go-review.googlesource.com/c/go/+/198758
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-10-04 00:22:44 +00:00
Damien Neil 170b8b4b12 all: add Unwrap and Is methods to various error types
Add Unwrap methods to types which wrap an underlying error:

  "encodinc/csv".ParseError
  "encoding/json".MarshalerError
  "net/http".transportReadFromServerError
  "net".OpError
  "net".DNSConfigError
  "net/url".Error
  "os/exec".Error
  "signal/internal/pty".PtyError
  "text/template".ExecError

Add os.ErrTemporary. A case could be made for putting this error
value in package net, since no exported error types in package os
include a Temporary method. However, syscall errors returned from
the os package do include this method.

Add Is methods to error types with a Timeout or Temporary method,
making errors.Is(err, os.Err{Timeout,Temporary}) equivalent to
testing the corresponding method:

  "context".DeadlineExceeded
  "internal/poll".TimeoutError
  "net".adrinfoErrno
  "net".OpError
  "net".DNSError
  "net/http".httpError
  "net/http".tlsHandshakeTimeoutError
  "net/pipe".timeoutError
  "net/url".Error

Updates #30322
Updates #29934

Change-Id: I409fb20c072ea39116ebfb8c7534d493483870dc
Reviewed-on: https://go-review.googlesource.com/c/go/+/170037
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
2019-05-04 16:14:12 +00:00
Brad Fitzpatrick 06c9ccdfc7 os/exec: always set SYSTEMROOT on Windows if not listed in Cmd.Env
Fixes #25210

Change-Id: If27b61776154dae9b9b67bf4e4f5faa785d98105
Reviewed-on: https://go-review.googlesource.com/c/go/+/174318
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-04-29 19:08:13 +00:00
Josh Bleecher Snyder 6249ea2f39 os/exec: add Cmd.String
The initial implementation is intentionally simple.
Let's see how far it gets us.

Fixes #30638

Change-Id: I240afae2b401744ab2ff2a69952c4eb0fd3feb56
Reviewed-on: https://go-review.googlesource.com/c/go/+/168518
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-21 13:19:55 +00:00
Daniel Martí d1887676d9 os/exec: less allocs in the common case
When Stdin, Stdout, and Stderr are nil, there are no goroutines to keep
track of, so we don't need a channel.

And in startProcess, preallocate the right size for sysattr.Files,
saving a bit of space and a couple of slice growth allocs.

name            old time/op    new time/op    delta
ExecHostname-8     419µs ± 0%     417µs ± 1%    ~     (p=0.093 n=6+6)

name            old alloc/op   new alloc/op   delta
ExecHostname-8    6.40kB ± 0%    6.28kB ± 0%  -1.86%  (p=0.002 n=6+6)

name            old allocs/op  new allocs/op  delta
ExecHostname-8      34.0 ± 0%      31.0 ± 0%  -8.82%  (p=0.002 n=6+6)

Change-Id: Ic1d617f29e9c6431cdcadc7f9bb992750a6d5f48
Reviewed-on: https://go-review.googlesource.com/c/164801
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-04 09:45:46 +00:00
Daniel Martí 59712fd03d os/exec: preallocate for Cmd.childFiles
We're always going to add stdin, stdout, and stderr to childFiles, so
its length will be at least three. The final length will be those three
elements plus however many files were given via ExtraFiles.

Allocate for that final length directly, saving two slice growth allocs
in the common case where ExtraFiles is empty.

name        old time/op    new time/op    delta
ExecEcho-8     435µs ± 0%     435µs ± 0%    ~     (p=0.394 n=6+6)

name        old alloc/op   new alloc/op   delta
ExecEcho-8    6.39kB ± 0%    6.37kB ± 0%  -0.39%  (p=0.002 n=6+6)

name        old allocs/op  new allocs/op  delta
ExecEcho-8      36.0 ± 0%      34.0 ± 0%  -5.56%  (p=0.002 n=6+6)

Change-Id: Ib702c0da1e43f0a55ed937af6d45fca6a170e8f3
Reviewed-on: https://go-review.googlesource.com/c/164898
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-03 17:45:46 +00:00
Josh Bleecher Snyder beadf433c3 os/exec: provide map size hint in dedupEnvCase
The common case is that most env vars are distinct;
optimize for that.

name        old time/op    new time/op    delta
ExecEcho-8    2.16ms ± 3%    2.14ms ± 1%     ~     (p=0.315 n=10+10)

name        old alloc/op   new alloc/op   delta
ExecEcho-8    7.87kB ± 0%    6.35kB ± 0%  -19.31%  (p=0.000 n=9+10)

name        old allocs/op  new allocs/op  delta
ExecEcho-8      72.0 ± 0%      69.0 ± 0%   -4.17%  (p=0.000 n=10+10)

Change-Id: I42bb696c6862f2ea12c5cbd2f24c64336a7a759a
Reviewed-on: https://go-review.googlesource.com/c/164960
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-02 20:11:47 +00:00
Giovanni Bajo 1d15354fb9 os/exec: document how to do special args quoting on Windows
Updates #27199

Change-Id: I5cb6540266901697d3558ce75b8de63b1bfc2ce0
Reviewed-on: https://go-review.googlesource.com/132695
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
2018-09-01 04:45:46 +00:00
Adam Shannon 6f96cf2793 os/exec: document ExtraFiles is not supported on windows
Fixes #26182

Change-Id: I1181e191f4742f166c9b67a6f41332a237cf0ede
Reviewed-on: https://go-review.googlesource.com/123855
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-07-13 22:29:48 +00:00
Tim Cooper 155aefe0c1 os/exec: remove "binary" when talking about executables
The use of binary was incorrect as executable files can also be scripts.

The docs for Error are also reworded. The old docs implied that Error was
returned when attempting to start an executable, which is not correct: it
was returned by LookPath when the file was not found or did not have the
attributes of an executable.

Change-Id: I757a44b16612936df4498b43c45c12e4c14956d2
Reviewed-on: https://go-review.googlesource.com/90315
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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2018-04-17 05:05:45 +00:00
Austin Clements 3ee8c3cc0b os: document inheritance of thread state over exec
Fixes #23570.

Change-Id: I462ada2960d710c2c94dc22a59d292703d83f612
Reviewed-on: https://go-review.googlesource.com/90255
Reviewed-by: Russ Cox <rsc@golang.org>
2018-01-26 18:54:04 +00:00
Tom Lanyon c866110689 os/exec: Stdout/Stderr doc cleanup.
Following comments on CL 76320.

Breaks Cmd.Std{out,err} doc into three paragraphs and updates Cmd.Stdin
formatting to match.

Fixes an erroneous reference to Stdin in the output goroutine comment, while
keeping the wording consistent between Stdin and Stdout/Stderr.

Change-Id: I186a0e2d4b85dfb939443a17e62a1eb2ef64b1bf
Reviewed-on: https://go-review.googlesource.com/79595
Reviewed-by: Rob Pike <r@golang.org>
2017-11-23 20:01:56 +00:00