1 files changed, 146 insertions, 0 deletions
diff --git a/src/tailer/tailerpp.cc b/src/tailer/tailerpp.cc
new file mode 100644
index 0000000..1ea0a9e
--- /dev/null
+++ b/src/tailer/tailerpp.cc
@@ -0,0 +1,146 @@
+/**
+ * Copyright (c) 2021, 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.
+ */
+
+#include "tailerpp.hh"
+
+#include <unistd.h>
+
+namespace tailer {
+
+int
+readall(int sock, void* buf, size_t len)
+{
+    char* cbuf = (char*) buf;
+    off_t offset = 0;
+
+    while (len > 0) {
+        ssize_t rc = read(sock, &cbuf[offset], len);
+
+        if (rc == -1) {
+            switch (errno) {
+                case EAGAIN:
+                case EINTR:
+                    break;
+                default:
+                    return -1;
+            }
+        } else if (rc == 0) {
+            errno = EIO;
+            return -1;
+        } else {
+            len -= rc;
+            offset += rc;
+        }
+    }
+
+    return 0;
+}
+
+Result<packet, std::string>
+read_packet(int fd)
+{
+    tailer_packet_type_t type;
+
+    if (readall(fd, &type, sizeof(type)) == -1) {
+        return Ok(packet{packet_eof{}});
+    }
+    switch (type) {
+        case TPT_ERROR: {
+            packet_error pe;
+
+            TRY(read_payloads_into(fd, pe.pe_path, pe.pe_msg));
+            return Ok(packet{pe});
+        }
+        case TPT_ANNOUNCE: {
+            packet_announce pa;
+
+            TRY(read_payloads_into(fd, pa.pa_uname));
+            return Ok(packet{pa});
+        }
+        case TPT_OFFER_BLOCK: {
+            packet_offer_block pob;
+
+            TRY(read_payloads_into(fd,
+                                   pob.pob_root_path,
+                                   pob.pob_path,
+                                   pob.pob_mtime,
+                                   pob.pob_offset,
+                                   pob.pob_length,
+                                   pob.pob_hash));
+            return Ok(packet{pob});
+        }
+        case TPT_TAIL_BLOCK: {
+            packet_tail_block ptb;
+
+            TRY(read_payloads_into(fd,
+                                   ptb.ptb_root_path,
+                                   ptb.ptb_path,
+                                   ptb.ptb_mtime,
+                                   ptb.ptb_offset,
+                                   ptb.ptb_bits));
+            return Ok(packet{ptb});
+        }
+        case TPT_SYNCED: {
+            packet_synced ps;
+
+            TRY(read_payloads_into(fd, ps.ps_root_path, ps.ps_path));
+            return Ok(packet{ps});
+        }
+        case TPT_LINK_BLOCK: {
+            packet_link pl;
+
+            TRY(read_payloads_into(
+                fd, pl.pl_root_path, pl.pl_path, pl.pl_link_value));
+            return Ok(packet{pl});
+        }
+        case TPT_PREVIEW_ERROR: {
+            packet_preview_error ppe;
+
+            TRY(read_payloads_into(fd, ppe.ppe_id, ppe.ppe_path, ppe.ppe_msg));
+            return Ok(packet{ppe});
+        }
+        case TPT_PREVIEW_DATA: {
+            packet_preview_data ppd;
+
+            TRY(read_payloads_into(fd, ppd.ppd_id, ppd.ppd_path, ppd.ppd_bits));
+            return Ok(packet{ppd});
+        }
+        case TPT_POSSIBLE_PATH: {
+            packet_possible_path ppp;
+
+            TRY(read_payloads_into(fd, ppp.ppp_path));
+            return Ok(packet{ppp});
+        }
+        default:
+            assert(0);
+            break;
+    }
+}
+
+}  // namespace tailer