Merging upstream version 0.12.2.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 248 insertions, 0 deletions

diff --git a/src/base/auto_fd.cc b/src/base/auto_fd.cc
new file mode 100644
index 0000000..0853c3a
--- /dev/null
+++ b/src/base/auto_fd.cc
@@ -0,0 +1,248 @@
+/**
+ * Copyright (c) 2023, Timothy Stack
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * * Neither the name of Timothy Stack nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * @file auto_fd.cc
+ */
+
+#include "auto_fd.hh"
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "lnav_log.hh"
+
+int
+auto_fd::pipe(auto_fd* af)
+{
+    int retval, fd[2];
+
+    require(af != nullptr);
+
+    if ((retval = ::pipe(fd)) == 0) {
+        af[0] = fd[0];
+        af[1] = fd[1];
+    }
+
+    return retval;
+}
+
+auto_fd
+auto_fd::dup_of(int fd)
+{
+    if (fd == -1) {
+        return auto_fd{};
+    }
+
+    auto new_fd = ::dup(fd);
+
+    if (new_fd == -1) {
+        throw std::bad_alloc();
+    }
+
+    return auto_fd(new_fd);
+}
+
+Result<auto_fd, std::string>
+auto_fd::openpt(int flags)
+{
+    auto rc = posix_openpt(flags);
+    if (rc == -1) {
+        return Err(fmt::format(FMT_STRING("posix_openpt() failed: {}"),
+                               strerror(errno)));
+    }
+
+    return Ok(auto_fd{rc});
+}
+
+auto_fd::auto_fd(int fd) : af_fd(fd)
+{
+    require(fd >= -1);
+}
+
+auto_fd::auto_fd(auto_fd&& af) noexcept : af_fd(af.release()) {}
+
+auto_fd
+auto_fd::dup() const
+{
+    int new_fd;
+
+    if (this->af_fd == -1 || (new_fd = ::dup(this->af_fd)) == -1) {
+        throw std::bad_alloc();
+    }
+
+    return auto_fd{new_fd};
+}
+
+auto_fd::~auto_fd()
+{
+    this->reset();
+}
+
+void
+auto_fd::reset(int fd)
+{
+    require(fd >= -1);
+
+    if (this->af_fd != fd) {
+        if (this->af_fd != -1) {
+            switch (this->af_fd) {
+                case STDIN_FILENO:
+                case STDOUT_FILENO:
+                case STDERR_FILENO:
+                    break;
+                default:
+                    close(this->af_fd);
+                    break;
+            }
+        }
+        this->af_fd = fd;
+    }
+}
+
+void
+auto_fd::close_on_exec() const
+{
+    if (this->af_fd == -1) {
+        return;
+    }
+    log_perror(fcntl(this->af_fd, F_SETFD, FD_CLOEXEC));
+}
+
+void
+auto_fd::non_blocking() const
+{
+    auto fl = fcntl(this->af_fd, F_GETFL, 0);
+    if (fl < 0) {
+        return;
+    }
+
+    log_perror(fcntl(this->af_fd, F_SETFL, fl | O_NONBLOCK));
+}
+
+auto_fd&
+auto_fd::operator=(int fd)
+{
+    require(fd >= -1);
+
+    this->reset(fd);
+    return *this;
+}
+
+Result<void, std::string>
+auto_fd::write_fully(string_fragment sf)
+{
+    while (!sf.empty()) {
+        auto rc = write(this->af_fd, sf.data(), sf.length());
+
+        if (rc < 0) {
+            return Err(
+                fmt::format(FMT_STRING("failed to write {} bytes to FD {}"),
+                            sf.length(),
+                            this->af_fd));
+        }
+
+        sf = sf.substr(rc);
+    }
+
+    return Ok();
+}
+
+Result<auto_pipe, std::string>
+auto_pipe::for_child_fd(int child_fd)
+{
+    auto_pipe retval(child_fd);
+
+    if (retval.open() == -1) {
+        return Err(std::string(strerror(errno)));
+    }
+
+    return Ok(std::move(retval));
+}
+
+auto_pipe::auto_pipe(int child_fd, int child_flags)
+    : ap_child_flags(child_flags), ap_child_fd(child_fd)
+{
+    switch (child_fd) {
+        case STDIN_FILENO:
+            this->ap_child_flags = O_RDONLY;
+            break;
+        case STDOUT_FILENO:
+        case STDERR_FILENO:
+            this->ap_child_flags = O_WRONLY;
+            break;
+    }
+}
+
+void
+auto_pipe::after_fork(pid_t child_pid)
+{
+    int new_fd;
+
+    switch (child_pid) {
+        case -1:
+            this->close();
+            break;
+        case 0:
+            if (this->ap_child_flags == O_RDONLY) {
+                this->write_end().reset();
+                if (this->read_end().get() == -1) {
+                    this->read_end() = ::open("/dev/null", O_RDONLY);
+                }
+                new_fd = this->read_end().get();
+            } else {
+                this->read_end().reset();
+                if (this->write_end().get() == -1) {
+                    this->write_end() = ::open("/dev/null", O_WRONLY);
+                }
+                new_fd = this->write_end().get();
+            }
+            if (this->ap_child_fd != -1) {
+                if (new_fd != this->ap_child_fd) {
+                    dup2(new_fd, this->ap_child_fd);
+                    this->close();
+                }
+            }
+            break;
+        default:
+            if (this->ap_child_flags == O_RDONLY) {
+                this->read_end().reset();
+            } else {
+                this->write_end().reset();
+            }
+            break;
+    }
+}
+
+int
+auto_pipe::open()
+{
+    int retval = auto_fd::pipe(this->ap_fd);
+    this->ap_fd[0].close_on_exec();
+    this->ap_fd[1].close_on_exec();
+    return retval;
+}