1 files changed, 142 insertions, 0 deletions
diff --git a/fitsy/socketgz.C b/fitsy/socketgz.C
new file mode 100644
index 0000000..56dc4da
--- /dev/null
+++ b/fitsy/socketgz.C
@@ -0,0 +1,142 @@
+// Copyright (C) 1999-2018
+// Smithsonian Astrophysical Observatory, Cambridge, MA, USA
+// For conditions of distribution and use, see copyright notice in "copyright"
+
+#include "socketgz.h"
+#include "util.h"
+
+#ifndef __WIN32
+
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
+#define HEAD_CRC     0x02 /* bit 1 set: header CRC present */
+#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define COMMENT      0x10 /* bit 4 set: file comment present */
+#define RESERVED     0xE0 /* bits 5..7: reserved */
+
+FitsSocketGZ::FitsSocketGZ(int s, const char* ext) 
+{
+  parse(ext);
+  if (!valid_)
+    return;
+
+  // reset
+  valid_ =0;
+
+  if (!s)
+    return;
+
+  stream_ = new gzStream_;
+  stream_->id = s;
+  stream_->transparent = 0;
+  memset(stream_->header,'\0',2);
+  stream_->useHeader = 0;
+  stream_->buf = new unsigned char[B4KB];
+
+  // magic bytes
+  if (recv(stream_->id , stream_->header, 2, 0) != 2) {
+    internalError("Fitsy++ socketgz can't read magic bytes in header");
+    return;
+  }
+
+  if (stream_->header[0] != 0x1f || stream_->header[1] != 0x8b) {
+    stream_->transparent = 1;
+    stream_->useHeader = 1;
+  }
+  else {
+    ((z_stream*)stream_)->next_in = NULL;
+    ((z_stream*)stream_)->avail_in = 0;
+    ((z_stream*)stream_)->zalloc = NULL;
+    ((z_stream*)stream_)->zfree = NULL;
+    ((z_stream*)stream_)->opaque = NULL;
+
+    if (inflateInit2((z_stream*)stream_, -MAX_WBITS) != Z_OK) {
+      internalError("Fitsy++ socketgz inflateInit error");
+      return;
+    }
+
+    unsigned char buf[128];
+
+    // method/flags
+    if (recv(stream_->id , buf, 2, 0) != 2) {
+      internalError("Fitsy++ socketgz can't read method/flags bytes in header");
+      return;
+    }
+    int method = buf[0];
+    int flags = buf[1];
+
+    if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
+      internalError("Fitsy++ socketgz bad method/flags");
+      return;
+    }
+
+    // Discard time, xflags and OS code
+    if (recv(stream_->id , buf, 6, 0) != 6) {
+      internalError("Fitsy++ socketgz can't read time/xflags/os bytes in header");
+      return;
+    }
+
+    // skip the extra field
+    if ((flags & EXTRA_FIELD) != 0) {
+      if (recv(stream_->id , buf, 2, 0) != 2) {
+	internalError("Fitsy++ socketgz can't read extra field length bytes in header");
+	return;
+      }
+
+      int len  =  buf[0];
+      len += buf[1]<<8;
+
+      if (recv(stream_->id , buf, len, 0) != len) {
+	internalError("Fitsy++ socketgz can't read extra field bytes in header");
+	return;
+      }
+    }
+
+    // skip the original file name
+    if ((flags & ORIG_NAME) != 0) { 
+      while (recv(stream_->id , buf, 1, 0) == 1 && buf[0] != 0) ;
+    }
+
+    // skip the .gz file comment
+    if ((flags & COMMENT) != 0) {
+      while (recv(stream_->id , buf, 1, 0) == 1 && buf[0] != 0) ;
+    }
+
+    // skip the header crc
+    if ((flags & HEAD_CRC) != 0) {
+      if (recv(stream_->id , buf, 2, 0) != 2) {
+	internalError("Fitsy++ socketgz can't read header crc bytes in header");
+	return;
+      }
+    }
+  }
+
+  if (DebugGZ)
+    cerr << "inflateInt Complete" << endl;
+
+  // so far, so good
+  valid_ = 1;
+}
+
+FitsSocketGZ::~FitsSocketGZ() 
+{
+  if (stream_->buf)
+    delete [] stream_->buf;
+  if (stream_)
+    delete stream_;
+  stream_ = NULL;
+}
+
+#else
+
+FitsSocketGZ::FitsSocketGZ(int s, const char* ext)
+{
+  valid_ =0;
+}
+
+FitsSocketGZ::~FitsSocketGZ() {}
+
+#endif