Extending gpfdist in Cloudberry Database to Support SFTP Protocol for Data Ingestion

gpfdist is a file distribution program in Cloudberry that can parallel
load external data into the database. However, it has the drawback
that data files must reside on the same machine as the tool.
Therefore,extending it to support the SFTP protocol can address the
above drawback and enable loading files from a remote server.

Add the libssh2 library and specify the link.

Implement remote data file reading using the libssh2 library with
gpfdist.

Extending gpfdist in Cloudberry Database to Support
SFTP Protocol for Data Ingestion -- add LIBSSH2 macro

ADD LIBSSH2 macro Label the SFTP-related code to indicate its
characteristics.

Author: 王平10304955

src/backend/Makefile

@@ -67,6 +67,7 @@ LIBS := $(filter-out -lreadline -ledit -ltermcap -lncurses -lcurses, $(LIBS))
 
 # Cloudberry uses threads in the backend
 LIBS := $(LIBS) -lpthread
+LIBS := $(LIBS) -lssh2
 
 ifeq ($(with_systemd),yes)
 LIBS += -lsystemd

src/backend/utils/misc/fstream/Makefile

@@ -9,7 +9,9 @@ subdir = src/backend/utils/misc/fstream
 top_builddir = ../../../../..
 include $(top_builddir)/src/Makefile.global
 
-override CPPFLAGS := -I$(srcdir) $(CPPFLAGS)
+LDFLAGS += -lssh2
+
+override CPPFLAGS := -I$(srcdir) $(CPPFLAGS) $(CPPFLAGS)
 
 OBJS = fstream.o gfile.o