figuring out behaviour of peg

[Malte Frank Gerdes]

Hi guile-user,

so i currently am trying to get further with the aprsing of Android
blueprints. Arun, gave the extremely helpful tip to use `pre-post-order'
for this, it seems to be a good way.

I just noticed a few things which i find odd about my grammar and i
don't see where it is coming from. (In the following example i'm using
the Android.bp file from libcutils of Android-10.0.0_r25). I'll show it
for the `list' non-terminal, but is is the same for the `map'
non-terminal (i guess because they have the same structure).

(defvar
     (var "libcutils_nonwindows_sources")
     (value (list (value (string "fs.cpp"))
               -->((value (string "hashmap.cpp"))
                   (value (string "multiuser.cpp"))
                   (value (string "socket_inaddr_any_server_unix.cpp"))
                   (value (string "socket_local_client_unix.cpp"))
                   (value (string "socket_local_server_unix.cpp"))
                   (value (string "socket_network_client_unix.cpp"))
                   (value (string "sockets_unix.cpp"))
                   (value (string "str_parms.cpp")))<-- )))

I highlighted two parens in this snippet, the question is: Why do they
even exist? - this *should* not be.

Multiple consecutive module definitions also are parsed into a
list. This *should* also not be the case. So is there a way to avoid
this? I guess it has something to do with ()* clauses in the grammar
definition?

Thanks in advance for any help!

Best Regards
Malte

Here are my test files, if you want to try it :)


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(use-modules (srfi srfi-1)
             (ice-9 peg)
             (ice-9 pretty-print)
             (ice-9 rdelim)
             (sxml transform))

(define *bp*
  (read-delimited "" (open-input-file (cadr (command-line))) 'concat))

(define-peg-string-patterns
  "blueprint  <-- (comment* (ws? defvar ws?)* module* comment*)* .*
   module     <-- rule ws? map ws?
   rule       <-- 'cc_binary_host' / 'cc_test_library' / 'cc_test_host' /
                 'cc_binary' / 'cc_test' /'cc_library_host_static' /
                 'cc_library_static' / 'cc_library_shared' /
                 'cc_library_headers' / 'cc_library' / 'cc_defaults' /
                 'cc_benchmark' / 'python_test_host' / 'genrule' / 'filegroup' /
                 'ndk_headers' / 'ndk_library' / 'llndk_library' /
                 'python_binary_host' / 'cc_prebuilt_binary' / 'prebuilt_etc' /
                 'python_defaults' / 'phony'
   defvar     <-- var ws? eq ws? value

   eq         < '='
   nl         < '\n'
   ws         < (' ' / '\t' / nl)+
   comma      < ','
   colon      < ':'
   maplb      < '{'
   maprb      < '}'
   listlb     < '['
   listrb     < ']'
   comment    < ws? '//' ( . !nl )* . ws?
   strb       < '\"'

   append     <-- '+'

   key        <-- ws? (comment ws?)* [-a-zA-Z0-9_]+
   bool       <-- 'true' / 'false'
   integer    <-- '-'? [0-9]+
   string     <-- strb (. !strb)* . strb
   map        <-- maplb ws? maprb / maplb ws? attribute (comma comment* ws? 
attribute)* comma? ws? maprb
   attribute  <-- key ws? colon ws? expr
   expr       <-- (value ws? append ws? &value)* value
   value      <-- bool / integer / string / map / list / var
   var        <-- [-a-zA-Z0-9_]+
   list       <-- listlb ws? listrb / listlb ws? comment* ws? value (comma 
comment* ws? value)* comma? ws? comment* listrb
")

(pretty-print (peg:tree (match-pattern blueprint *bp*)))


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--------------------------------------------------------------------------------


//
// Copyright (C) 2008 The Android Open Source Project
//
// 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.
//

// some files must not be compiled when building against Mingw
// they correspond to features not used by our host development tools
// which are also hard or even impossible to port to native Win32
libcutils_nonwindows_sources = [
    "fs.cpp",
    "hashmap.cpp",
    "multiuser.cpp",
    "socket_inaddr_any_server_unix.cpp",
    "socket_local_client_unix.cpp",
    "socket_local_server_unix.cpp",
    "socket_network_client_unix.cpp",
    "sockets_unix.cpp",
    "str_parms.cpp",
]

cc_library_headers {
    name: "libcutils_headers",
    vendor_available: true,
    recovery_available: true,
    host_supported: true,
    export_include_dirs: ["include"],
    target: {
        vendor: {
            override_export_include_dirs: ["include_vndk"],
        },
        linux_bionic: {
            enabled: true,
        },
        windows: {
            enabled: true,
        },
    },
}

cc_library {
    name: "libcutils",
    vendor_available: true,
    vndk: {
        enabled: true,
        support_system_process: true,
    },
    recovery_available: true,
    host_supported: true,
    srcs: [
        "config_utils.cpp",
        "canned_fs_config.cpp",
        "iosched_policy.cpp",
        "load_file.cpp",
        "native_handle.cpp",
        "record_stream.cpp",
        "sockets.cpp",
        "strdup16to8.cpp",
        "strdup8to16.cpp",
        "strlcpy.c",
        "threads.cpp",
    ],

    target: {
        linux_bionic: {
            enabled: true,
        },
        not_windows: {
            srcs: libcutils_nonwindows_sources + [
                "ashmem-host.cpp",
                "fs_config.cpp",
                "trace-host.cpp",
            ],
        },
        windows: {
            host_ldlibs: ["-lws2_32"],

            srcs: [
                "socket_inaddr_any_server_windows.cpp",
                "socket_network_client_windows.cpp",
                "sockets_windows.cpp",
                "trace-host.cpp",
            ],

            enabled: true,
            cflags: [
                "-D_GNU_SOURCE",
            ],
        },

        android: {
            srcs: libcutils_nonwindows_sources + [
                "android_get_control_file.cpp",
                "android_reboot.cpp",
                "ashmem-dev.cpp",
                "fs_config.cpp",
                "klog.cpp",
                "partition_utils.cpp",
                "properties.cpp",
                "qtaguid.cpp",
                "trace-dev.cpp",
                "uevent.cpp",
            ],
        },

        android_arm: {
            srcs: ["arch-arm/memset32.S"],
            sanitize: {
                misc_undefined: ["integer"],
            },
        },
        android_arm64: {
            srcs: ["arch-arm64/android_memset.S"],
            sanitize: {
                misc_undefined: ["integer"],
            },
        },

        android_mips: {
            srcs: ["arch-mips/android_memset.c"],
            sanitize: {
                misc_undefined: ["integer"],
            },
        },
        android_mips64: {
            srcs: ["arch-mips/android_memset.c"],
            sanitize: {
                misc_undefined: ["integer"],
            },
        },

        android_x86: {
            srcs: [
                "arch-x86/android_memset16.S",
                "arch-x86/android_memset32.S",
            ],
            // TODO: This is to work around b/29412086.
            // Remove once __mulodi4 is available and move the "sanitize" block
            // to the android target.
            sanitize: {
                misc_undefined: [],
            },
        },

        android_x86_64: {
            srcs: [
                "arch-x86_64/android_memset16.S",
                "arch-x86_64/android_memset32.S",
            ],
            sanitize: {
                misc_undefined: ["integer"],
            },
        },

        vendor: {
            exclude_srcs: [
                // qtaguid.cpp loads libnetd_client.so with dlopen().  Since
                // the interface of libnetd_client.so may vary between AOSP
                // releases, exclude qtaguid.cpp from the VNDK-SP variant.
                "qtaguid.cpp",
            ],
        }
    },

    shared_libs: [
        "liblog",
        "libbase",
    ],
    header_libs: [
        "libbase_headers",
        "libcutils_headers",
        "libutils_headers",
        "libprocessgroup_headers",
    ],
    export_header_lib_headers: [
        "libcutils_headers",
        "libprocessgroup_headers",
    ],
    local_include_dirs: ["include"],

    cflags: [
        "-Werror",
        "-Wall",
        "-Wextra",
    ],
}

cc_defaults {
    name: "libcutils_test_default",
    srcs: ["sockets_test.cpp"],

    target: {
        android: {
            srcs: [
                "android_get_control_file_test.cpp",
                "android_get_control_socket_test.cpp",
                "ashmem_test.cpp",
                "fs_config_test.cpp",
                "memset_test.cpp",
                "multiuser_test.cpp",
                "properties_test.cpp",
                "sched_policy_test.cpp",
                "str_parms_test.cpp",
                "trace-dev_test.cpp",
            ],
        },

        not_windows: {
            srcs: [
                "str_parms_test.cpp",
            ],
        },
    },

    cflags: [
        "-Wall",
        "-Wextra",
        "-Werror",
    ],
}

test_libraries = [
    "libcutils",
    "liblog",
    "libbase",
    "libjsoncpp",
    "libprocessgroup",
    "libcgrouprc",
]

cc_test {
    name: "libcutils_test",
    test_suites: ["device-tests"],
    defaults: ["libcutils_test_default"],
    host_supported: true,
    shared_libs: test_libraries,
}

cc_test {
    name: "libcutils_test_static",
    test_suites: ["device-tests"],
    defaults: ["libcutils_test_default"],
    static_libs: [
        "libc",
        "libcgrouprc_format",
    ] + test_libraries,
    stl: "libc++_static",

    target: {
        android: {
            static_executable: true,
        },
        windows: {
            host_ldlibs: ["-lws2_32"],

            enabled: true,
        },
    },
}


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