chelper: Move the host C code to a new klippy/chelper/ directory

Move the C code out of the main klippy/ directory and into its own
directory.  This reduces the clutter in the main klippy directory.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/chelper/__init__.py

@@ -0,0 +1,137 @@
+# Wrapper around C helper code
+#
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import os, logging
+import cffi
+
+
+######################################################################
+# c_helper.so compiling
+######################################################################
+
+COMPILE_CMD = "gcc -Wall -g -O2 -shared -fPIC -o %s %s"
+SOURCE_FILES = ['stepcompress.c', 'serialqueue.c', 'pyhelper.c']
+DEST_LIB = "c_helper.so"
+OTHER_FILES = ['list.h', 'serialqueue.h', 'pyhelper.h']
+
+defs_stepcompress = """
+    struct stepcompress *stepcompress_alloc(uint32_t max_error
+        , uint32_t queue_step_msgid, uint32_t set_next_step_dir_msgid
+        , uint32_t invert_sdir, uint32_t oid);
+    void stepcompress_free(struct stepcompress *sc);
+    int stepcompress_reset(struct stepcompress *sc, uint64_t last_step_clock);
+    int stepcompress_set_homing(struct stepcompress *sc, uint64_t homing_clock);
+    int stepcompress_queue_msg(struct stepcompress *sc, uint32_t *data, int len);
+
+    int32_t stepcompress_push(struct stepcompress *sc, double step_clock
+        , int32_t sdir);
+    int32_t stepcompress_push_const(struct stepcompress *sc, double clock_offset
+        , double step_offset, double steps, double start_sv, double accel);
+    int32_t stepcompress_push_delta(struct stepcompress *sc
+        , double clock_offset, double move_sd, double start_sv, double accel
+        , double height, double startxy_sd, double arm_d, double movez_r);
+
+    struct steppersync *steppersync_alloc(struct serialqueue *sq
+        , struct stepcompress **sc_list, int sc_num, int move_num);
+    void steppersync_free(struct steppersync *ss);
+    void steppersync_set_time(struct steppersync *ss
+        , double time_offset, double mcu_freq);
+    int steppersync_flush(struct steppersync *ss, uint64_t move_clock);
+"""
+
+defs_serialqueue = """
+    #define MESSAGE_MAX 64
+    struct pull_queue_message {
+        uint8_t msg[MESSAGE_MAX];
+        int len;
+        double sent_time, receive_time;
+    };
+
+    struct serialqueue *serialqueue_alloc(int serial_fd, int write_only);
+    void serialqueue_exit(struct serialqueue *sq);
+    void serialqueue_free(struct serialqueue *sq);
+    struct command_queue *serialqueue_alloc_commandqueue(void);
+    void serialqueue_free_commandqueue(struct command_queue *cq);
+    void serialqueue_send(struct serialqueue *sq, struct command_queue *cq
+        , uint8_t *msg, int len, uint64_t min_clock, uint64_t req_clock);
+    void serialqueue_encode_and_send(struct serialqueue *sq
+        , struct command_queue *cq, uint32_t *data, int len
+        , uint64_t min_clock, uint64_t req_clock);
+    void serialqueue_pull(struct serialqueue *sq, struct pull_queue_message *pqm);
+    void serialqueue_set_baud_adjust(struct serialqueue *sq, double baud_adjust);
+    void serialqueue_set_clock_est(struct serialqueue *sq, double est_freq
+        , double last_clock_time, uint64_t last_clock);
+    void serialqueue_get_stats(struct serialqueue *sq, char *buf, int len);
+    int serialqueue_extract_old(struct serialqueue *sq, int sentq
+        , struct pull_queue_message *q, int max);
+"""
+
+defs_pyhelper = """
+    void set_python_logging_callback(void (*func)(const char *));
+    double get_monotonic(void);
+"""
+
+# Return the list of file modification times
+def get_mtimes(srcdir, filelist):
+    out = []
+    for filename in filelist:
+        pathname = os.path.join(srcdir, filename)
+        try:
+            t = os.path.getmtime(pathname)
+        except os.error:
+            continue
+        out.append(t)
+    return out
+
+# Check if the code needs to be compiled
+def check_build_code(srcdir, target, sources, cmd, other_files=[]):
+    src_times = get_mtimes(srcdir, sources + other_files)
+    obj_times = get_mtimes(srcdir, [target])
+    if not obj_times or max(src_times) > min(obj_times):
+        logging.info("Building C code module %s", target)
+        srcfiles = [os.path.join(srcdir, fname) for fname in sources]
+        destlib = os.path.join(srcdir, target)
+        os.system(cmd % (destlib, ' '.join(srcfiles)))
+
+FFI_main = None
+FFI_lib = None
+pyhelper_logging_callback = None
+
+# Return the Foreign Function Interface api to the caller
+def get_ffi():
+    global FFI_main, FFI_lib, pyhelper_logging_callback
+    if FFI_lib is None:
+        srcdir = os.path.dirname(os.path.realpath(__file__))
+        check_build_code(srcdir, DEST_LIB, SOURCE_FILES, COMPILE_CMD
+                         , OTHER_FILES)
+        FFI_main = cffi.FFI()
+        FFI_main.cdef(defs_stepcompress)
+        FFI_main.cdef(defs_serialqueue)
+        FFI_main.cdef(defs_pyhelper)
+        FFI_lib = FFI_main.dlopen(os.path.join(srcdir, DEST_LIB))
+        # Setup error logging
+        def logging_callback(msg):
+            logging.error(FFI_main.string(msg))
+        pyhelper_logging_callback = FFI_main.callback(
+            "void(const char *)", logging_callback)
+        FFI_lib.set_python_logging_callback(pyhelper_logging_callback)
+    return FFI_main, FFI_lib
+
+
+######################################################################
+# hub-ctrl hub power controller
+######################################################################
+
+HC_COMPILE_CMD = "gcc -Wall -g -O2 -o %s %s -lusb"
+HC_SOURCE_FILES = ['hub-ctrl.c']
+HC_SOURCE_DIR = '../lib/hub-ctrl'
+HC_TARGET = "hub-ctrl"
+HC_CMD = "sudo %s/hub-ctrl -h 0 -P 2 -p %d"
+
+def run_hub_ctrl(enable_power):
+    srcdir = os.path.dirname(os.path.realpath(__file__))
+    hubdir = os.path.join(srcdir, HC_SOURCE_DIR)
+    check_build_code(hubdir, HC_TARGET, HC_SOURCE_FILES, HC_COMPILE_CMD)
+    os.system(HC_CMD % (hubdir, enable_power))