1# Copyright (C) 2010 The Android Open Source Project 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# http://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12# See the License for the specific language governing permissions and 13# limitations under the License. 14# 15 16# This script is used to generate a Makefile fragment that will be evaluated 17# at runtime by the NDK build system during its initialization pass. 18# 19# The purpose of this generated fragment is to define a function, named 20# 'cygwin-to-host-path' that will transform a Cygwin-specific path into the 21# corresponding Windows specific one, i.e. calling 22# 23# $(call cygwin-to-host-path,/cygdrive/c/Stuff/) --> c:/Stuff 24# 25# A naive implementation of this function would be the following: 26# 27# cygwin-to-host-path = $(shell cygpath -m $1) 28# 29# Unfortunately, calling 'cygpath -m' from GNU Make is horridly slow and people 30# have complained that this was adding several minutes to their builds, even in 31# the case where there is nothing to do. 32# 33# The script expects its input to be the output of the Cygwin "mount" command 34# as in: 35# 36# C:/cygwin/bin on /usr/bin type ntfs (binary,auto) 37# C:/cygwin/lib on /usr/lib type ntfs (binary,auto) 38# C:/cygwin on / type ntfs (binary,auto) 39# C: on /cygdrive/c type ntfs (binary,posix=0,user,noumount,auto) 40# D: on /cygdrive/d type udf (binary,posix=0,user,noumount,auto) 41# 42# The script's output will be passed to the GNU Make 'eval' function 43# and will look like: 44# 45# $(patsubst /%,C:/cygwin/, 46# $(patsubst /usr/bin/%,C:/cygwin/bin/, 47# $(patsubst /usr/lib/%,C:/cygwin/lib/, 48# $(patsubst /cygdrive/C/%,C:/, 49# $(patsubst /cygdrive/D/%,D:/, 50# $(patsubst /cygdrive/c/%,C:/, 51# $(patsubst /cygdrive/d/%,D:/,$1))))) 52# 53BEGIN { 54 # setup our count 55 count = 0 56} 57 58$2 == "on" { 59 # record a new (host-path,cygwin-path) pair 60 count ++ 61 host[count] = $1 62 cygwin[count] = $3 63} 64 65END { 66 # Drive letters are special cases because we must match both 67 # the upper and lower case versions to the same drive, i.e. 68 # if "mount" lists that /cygdrive/c maps to C:, we need to 69 # map both /cygdrive/c and /cygdrive/C to C: in our final rules. 70 # 71 count1 = count 72 for (nn = 1; nn <= count1; nn++) { 73 if (!match(host[nn],"^[A-Za-z]:$")) { 74 # not a driver letter mapping, skip this pair 75 continue 76 } 77 letter = substr(host[nn],1,1) 78 lo = tolower(letter) 79 up = toupper(letter) 80 81 # If the cygwin path ends in /<lo>, then substitute it with /<up> 82 # to create a new pair. 83 if (match(cygwin[nn],"/"lo"$")) { 84 count++ 85 host[count] = host[nn] 86 cygwin[count] = substr(cygwin[nn],1,length(cygwin[nn])-1) up 87 continue 88 } 89 90 # If the cygwin path ends in /<up>, then substitute it with /<lo> 91 # to create a new pair. 92 if (match(cygwin[nn],"/"up"$")) { 93 count++ 94 host[count] = host[nn] 95 cygwin[count] = substr(cygwin[nn],1,length(cygwin[nn])-1) lo 96 continue 97 } 98 } 99 100 # We have recorded all (host,cygwin) path pairs, 101 # now try to sort them so that the ones with the longest cygwin path 102 # appear first 103 for (ii = 2; ii <= count; ii++) { 104 for (jj = ii-1; jj > 0; jj--) { 105 if (length(cygwin[jj]) > length(cygwin[jj+1])) { 106 break; 107 } 108 if (length(cygwin[jj]) == length(cygwin[jj+1]) && 109 cygwin[jj] > cygwin[jj+1]) { 110 break 111 } 112 tmp = cygwin[jj] 113 cygwin[jj] = cygwin[jj+1] 114 cygwin[jj+1] = tmp 115 tmp = host[jj] 116 host[jj] = host[jj+1] 117 host[jj+1] = tmp 118 } 119 } 120 121 # build/core/init.mk defines VERBOSE to 1 when it needs to dump the 122 # list of substitutions in a human-friendly format, generally when 123 # NDK_LOG is defined in the environment 124 # 125 # Otherwise, just generate the corresponding Make function definition 126 # 127 if (VERBOSE == 1) { 128 for (nn = 1; nn <= count; nn++) { 129 printf( "$(info %s => %s)", cygwin[nn], host[nn]); 130 } 131 } else { 132 RESULT = "$1" 133 for (nn = 1; nn <= count; nn++) { 134 add_drive_rule(host[nn], cygwin[nn]) 135 } 136 print RESULT 137 } 138} 139 140function add_drive_rule (hostpath,cygpath) 141{ 142 if (cygpath == "/") { 143 # Special case for / 144 RESULT = "$(patsubst /%," hostpath "/%,\n" RESULT ")" 145 return 146 } 147 # default rule otherwise 148 RESULT = "$(patsubst " cygpath "/%," hostpath "/%,\n" RESULT ")" 149} 150