docs: better docs, mv doxygen to sphinx

This patch refactors the VPP sphinx docs
in order to make it easier to consume
for external readers as well as VPP developers.

It also makes sphinx the single source
of documentation, which simplifies maintenance
and operation.

Most important updates are:

- reformat the existing documentation as rst
- split RELEASE.md and move it into separate rst files
- remove section 'events'
- remove section 'archive'
- remove section 'related projects'
- remove section 'feature by release'
- remove section 'Various links'
- make (Configuration reference, CLI docs,
  developer docs) top level items in the list
- move 'Use Cases' as part of 'About VPP'
- move 'Troubleshooting' as part of 'Getting Started'
- move test framework docs into 'Developer Documentation'
- add a 'Contributing' section for gerrit,
  docs and other contributer related infos
- deprecate doxygen and test-docs targets
- redirect the "make doxygen" target to "make docs"

Type: refactor

Change-Id: I552a5645d5b7964d547f99b1336e2ac24e7c209f
Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>
Signed-off-by: Andrew Yourtchenko <ayourtch@gmail.com>

1 files changed, 306 insertions, 0 deletions

diff --git a/docs/_scripts/siphon/generate.py b/docs/_scripts/siphon/generate.py
new file mode 100644
index 00000000000..2ae5a1b6f1b
--- /dev/null
+++ b/docs/_scripts/siphon/generate.py
@@ -0,0 +1,306 @@
+# Copyright (c) 2016 Comcast Cable Communications Management, LLC.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Generate .siphon source fragments for later processing
+
+import json
+import logging
+import os
+import re
+
+"""List of (regexp, siphon_name) tuples for matching the start of C
+   initializer blocks in source files. Each siphon class registers
+   themselves on this list."""
+siphon_patterns = []
+
+class Generate(object):
+    """Matches a siphon comment block start"""
+    siphon_block_start = re.compile("^\s*/\*\?\s*(.*)$")
+
+    """Matches a siphon comment block stop"""
+    siphon_block_stop = re.compile("^(.*)\s*\?\*/\s*$")
+
+    """Siphon block directive delimiter"""
+    siphon_block_delimiter = "%%"
+
+    """Matches a siphon block directive such as
+       '%clicmd:group_label Debug CLI%'"""
+    siphon_block_directive = re.compile("(%s)\s*([a-zA-Z0-9_:]+)\s+(.*)\s*(%s)" % \
+            (siphon_block_delimiter, siphon_block_delimiter))
+
+    """Matches the start of an initializer block"""
+    siphon_initializer = re.compile("\s*=")
+
+    """Collated output for each siphon"""
+    output = None
+
+    """Directory prefix to strip from input filenames to keep things tidy."""
+    input_prefix = None
+
+    """List of known siphons"""
+    known_siphons = None
+
+    """Logging handler"""
+    log = None
+
+
+    def __init__(self, output_directory, input_prefix):
+        super(Generate, self).__init__()
+        self.log = logging.getLogger("siphon.generate")
+
+        # Build a list of known siphons
+        self.known_siphons = []
+        for item in siphon_patterns:
+            siphon = item[1]
+            if siphon not in self.known_siphons:
+                self.known_siphons.append(siphon)
+
+        # Setup information for siphons we know about
+        self.output = {}
+        for siphon in self.known_siphons:
+            self.output[siphon] = {
+                    "file": "%s/%s.siphon" % (output_directory, siphon),
+                    "global": {},
+                    "items": [],
+                }
+
+        self.input_prefix = input_prefix
+
+
+    """
+    count open and close braces in str
+    return (0, index) when braces were found and count becomes 0.
+    index indicates the position at which the last closing brace was
+    found.
+    return (-1, -1) if a closing brace is found before any opening one.
+    return (count, -1) if not all opening braces are closed, count is the
+    current depth
+    """
+    def count_braces(self, str, count=0, found=False):
+        for index in range(0, len(str)):
+            if str[index] == '{':
+                count += 1;
+                found = True
+            elif str[index] == '}':
+                if count == 0:
+                    # means we never found an open brace
+                    return (-1, -1)
+                count -= 1;
+
+            if count == 0 and found:
+                return (count, index)
+
+        return (count, -1)
+
+    def parse(self, filename):
+        # Strip the current directory off the start of the
+        # filename for brevity
+        if filename[0:len(self.input_prefix)] == self.input_prefix:
+            filename = filename[len(self.input_prefix):]
+            if filename[0] == "/":
+                filename = filename[1:]
+
+        # Work out the abbreviated directory name
+        directory = os.path.dirname(filename)
+        if directory[0:2] == "./":
+            directory = directory[2:]
+        elif directory[0:len(self.input_prefix)] == self.input_prefix:
+            directory = directory[len(self.input_prefix):]
+        if directory[0] == "/":
+            directory = directory[1:]
+
+        # Open the file and explore its contents...
+        self.log.info("Siphoning from %s." % filename)
+        directives = {}
+        with open(filename) as fd:
+            siphon = None
+            close_siphon = None
+            siphon_block = ""
+            in_block = False
+            line_num = 0
+            siphon_line = 0
+
+            for line in fd:
+                line_num += 1
+                str = line[:-1] # filter \n
+
+                """See if there is a block directive and if so extract it"""
+                def process_block_directive(str, directives):
+                    m = self.siphon_block_directive.search(str)
+                    if m is not None:
+                        k = m.group(2)
+                        v = m.group(3).strip()
+                        directives[k] = v
+                        # Return only the parts we did not match
+                        return str[0:m.start(1)] + str[m.end(4):]
+
+                    return str
+
+                def process_block_prefix(str):
+                    if str.startswith(" * "):
+                        str = str[3:]
+                    elif str == " *":
+                        str = ""
+                    return str
+
+                if not in_block:
+                    # See if the line contains the start of a siphon doc block
+                    m = self.siphon_block_start.search(str)
+                    if m is not None:
+                        in_block = True
+                        t = m.group(1)
+
+                        # Now check if the block closes on the same line
+                        m = self.siphon_block_stop.search(t)
+                        if m is not None:
+                            t = m.group(1)
+                            in_block = False
+
+                        # Check for directives
+                        t = process_block_directive(t, directives)
+
+                        # Filter for normal comment prefixes
+                        t = process_block_prefix(t)
+
+                        # Add what is left
+                        siphon_block += t
+
+                        # Skip to next line
+                        continue
+
+                else:
+                    # Check to see if we have an end block marker
+                    m = self.siphon_block_stop.search(str)
+                    if m is not None:
+                        in_block = False
+                        t = m.group(1)
+                    else:
+                        t = str
+
+                    # Check for directives
+                    t = process_block_directive(t, directives)
+
+                    # Filter for normal comment prefixes
+                    t = process_block_prefix(t)
+
+                    # Add what is left
+                    siphon_block += t + "\n"
+
+                    # Skip to next line
+                    continue
+
+
+                if siphon is None:
+                    # Look for blocks we need to siphon
+                    for p in siphon_patterns:
+                        if p[0].match(str):
+                            siphon = [ p[1], str + "\n", 0 ]
+                            siphon_line = line_num
+
+                            # see if we have an initializer
+                            m = self.siphon_initializer.search(str)
+                            if m is not None:
+                                # count the braces on this line
+                                (count, index) = \
+                                    self.count_braces(str[m.start():])
+                                siphon[2] = count
+                                # TODO - it's possible we have the
+                                # initializer all on the first line
+                                # we should check for it, but also
+                                # account for the possibility that
+                                # the open brace is on the next line
+                                #if count == 0:
+                                #    # braces balanced
+                                #    close_siphon = siphon
+                                #    siphon = None
+                            else:
+                                # no initializer: close the siphon right now
+                                close_siphon = siphon
+                                siphon = None
+                else:
+                    # See if we should end the siphon here - do we have
+                    # balanced braces?
+                    (count, index) = self.count_braces(str,
+                            count=siphon[2], found=True)
+                    if count == 0:
+                        # braces balanced - add the substring and
+                        # close the siphon
+                        siphon[1] += str[:index+1] + ";\n"
+                        close_siphon = siphon
+                        siphon = None
+                    else:
+                        # add the whole string, move on
+                        siphon[2] = count
+                        siphon[1] += str + "\n"
+
+                if close_siphon is not None:
+                    # Write the siphoned contents to the right place
+                    siphon_name = close_siphon[0]
+
+                    # Copy directives for the file
+                    details = {}
+                    for key in directives:
+                        if ":" in key:
+                            (sn, label) = key.split(":")
+                            if sn == siphon_name:
+                                details[label] = directives[key]
+                        else:
+                            details[key] = directives[key]
+
+                    # Copy details for this block
+                    details['file'] = filename
+                    details['directory'] = directory
+                    details['line_start'] = siphon_line
+                    details['line_end'] = line_num
+                    details['siphon_block'] = siphon_block.strip()
+                    details["block"] = close_siphon[1]
+
+                    # Store the item
+                    self.output[siphon_name]['items'].append(details)
+
+                    # All done
+                    close_siphon = None
+                    siphon_block = ""
+
+            # Update globals
+            for key in directives.keys():
+                if ':' not in key:
+                    continue
+
+                if filename.endswith("/dir.dox"):
+                    # very special! use the parent directory name
+                    l = directory
+                else:
+                    l = filename
+
+                (sn, label) = key.split(":")
+
+                if sn not in self.output:
+                    self.output[sn] = {}
+                if 'global' not in self.output[sn]:
+                    self.output[sn]['global'] = {}
+                if l not in self.output[sn]['global']:
+                    self.output[sn]['global'][l] = {}
+
+                self.output[sn]['global'][l][label] = directives[key]
+
+    def deliver(self):
+        # Write out the data
+        for siphon in self.output.keys():
+            self.log.info("Saving siphon data %s." % siphon)
+            s = self.output[siphon]
+            with open(s['file'], "a") as fp:
+                json.dump(s, fp,
+                    separators=(',', ': '), indent=4, sort_keys=True)
+