From 82ee3d6a4e174c065c2c0dba0037ce30646e365f Mon Sep 17 00:00:00 2001
From: Kurtis Rader <krader@skepticism.us>
Date: Sun, 13 Aug 2017 15:24:08 -0700
Subject: [PATCH] Revert "Deduplication between INTERNAL_FUNCTION and
 INTERNAL_BLOCK_NODE"

This reverts commit 0594735714faf03e92863ebda67945a45521493e.
It was meant for the major branch.
---
 src/exec.cpp | 52 +++++++++++++++++++++++++++-------------------------
 1 file changed, 27 insertions(+), 25 deletions(-)

diff --git a/src/exec.cpp b/src/exec.cpp
index 891159005..72e615c30 100644
--- a/src/exec.cpp
+++ b/src/exec.cpp
@@ -685,28 +685,6 @@ void exec_job(parser_t &parser, job_t *j) {
             return true;
         };
 
-
-        //helper routine executed by INTERNAL_FUNCTION and INTERNAL_BLOCK_NODE to make sure
-        //an output buffer exists in case there is another command in the job chain that will
-        //be reading from this command's output.
-        auto verify_buffer_output = [&] () {
-            if (!p->is_last_in_job) {
-                // Be careful to handle failure, e.g. too many open fds.
-                block_output_io_buffer = io_buffer_t::create(STDOUT_FILENO, all_ios);
-                if (block_output_io_buffer.get() == NULL) {
-                    exec_error = true;
-                    job_mark_process_as_failed(j, p);
-                } else {
-                    // This looks sketchy, because we're adding this io buffer locally - they
-                    // aren't in the process or job redirection list. Therefore select_try won't
-                    // be able to read them. However we call block_output_io_buffer->read()
-                    // below, which reads until EOF. So there's no need to select on this.
-                    process_net_io_chain.push_back(block_output_io_buffer);
-                }
-            }
-        };
-
-
         switch (p->type) {
             case INTERNAL_FUNCTION: {
                 // Calls to function_get_definition might need to source a file as a part of
@@ -737,7 +715,20 @@ void exec_job(parser_t &parser, job_t *j) {
 
                 parser.forbid_function(func_name);
 
-                verify_buffer_output();
+                if (!p->is_last_in_job) {
+                    // Be careful to handle failure, e.g. too many open fds.
+                    block_output_io_buffer = io_buffer_t::create(STDOUT_FILENO, all_ios);
+                    if (block_output_io_buffer.get() == NULL) {
+                        exec_error = true;
+                        job_mark_process_as_failed(j, p);
+                    } else {
+                        // This looks sketchy, because we're adding this io buffer locally - they
+                        // aren't in the process or job redirection list. Therefore select_try won't
+                        // be able to read them. However we call block_output_io_buffer->read()
+                        // below, which reads until EOF. So there's no need to select on this.
+                        process_net_io_chain.push_back(block_output_io_buffer);
+                    }
+                }
 
                 if (!exec_error) {
                     internal_exec_helper(parser, def, NODE_OFFSET_INVALID, TOP,
@@ -751,7 +742,18 @@ void exec_job(parser_t &parser, job_t *j) {
             }
 
             case INTERNAL_BLOCK_NODE: {
-                verify_buffer_output();
+                if (!p->is_last_in_job) {
+                    block_output_io_buffer = io_buffer_t::create(STDOUT_FILENO, all_ios);
+                    if (block_output_io_buffer.get() == NULL) {
+                        // We failed (e.g. no more fds could be created).
+                        exec_error = true;
+                        job_mark_process_as_failed(j, p);
+                    } else {
+                        // See the comment above about it's OK to add an IO redirection to this
+                        // local buffer, even though it won't be handled in select_try.
+                        process_net_io_chain.push_back(block_output_io_buffer);
+                    }
+                }
 
                 if (!exec_error) {
                     internal_exec_helper(parser, wcstring(), p->internal_block_node, TOP,
@@ -860,7 +862,7 @@ void exec_job(parser_t &parser, job_t *j) {
                     const int fg = j->get_flag(JOB_FOREGROUND);
                     j->set_flag(JOB_FOREGROUND, false);
 
-                    //main loop may need to perform a blocking read from previous command's output.
+                    //main loop is performing a blocking read from previous command's output
                     //make sure read source is not blocked
                     unblock_previous();