diff options
| -rwxr-xr-x | scripts/depsort | 116 |
1 files changed, 115 insertions, 1 deletions
diff --git a/scripts/depsort b/scripts/depsort index 953260238..2293d9aa4 100755 --- a/scripts/depsort +++ b/scripts/depsort @@ -1,3 +1,117 @@ #!/bin/sh -e -awk '{ for (f=1;f<=NF;f++) { print $(f),$1 } }' | "$(dirname $(readlink -f ${0}))"/tsort +HERE="$(dirname $(readlink -f ${0}))"; +LIST="${HERE}/../.exclude"; + +#--------------------------------------------------------------- +# overview + +## +# Usage: +# +# $ ./scripts/deplist system | ./scripts/depsort +# +# This script reads a list of packages (stdin) of the form: +# +# pkg1 dep1 dep2 ... +# pkg2 ... +# +# and computes a topological sort, then prints to stdout. +# +# If the file called '$LIST' exists, it will be used as a filter +# to exclude those packages, their dependencies, and transitive +# dependencies as well, from the build plan. +# +# Entries must be one per line of the form REPO/PACKAGE: +# +# user/rust +# +# It is possible to end up with a surprisingly small build plan +# if a more essential package is excluded, so this mechanism +# should only be used to temporarily avoid problematic packages +# or known package families e.g. "all java-related". + + +#--------------------------------------------------------------- +# supporting routines + +## +# Appends text to the end of each line of stdin, in this case it +# is to assist 'grep' later on. +# +# We strictly search for ending in space or end of line instead +# of with the flag '-F', which is string literal, to avoid any +# partial and undesirable matches, e.g. 'foo' in 'foo3'. +# +# This is a function because it is used multiple times and may +# need to be updated in the future. +# +suffix () +{ + sed -e 's@$@\\( \\|$\\)@g'; +} + + +#--------------------------------------------------------------- +# initialization + +## +# We need to create a few temporary files in order to support +# handling transitive dependencies because it is not possible to +# reuse 'foo' as in: 'tee >( ... > foo) | bar -f foo'. +# +data=$(mktemp); # stdin +user=$(mktemp); # processed '$LIST' +real=$(mktemp); # processed derivation of dependencies + +## +# Capture stdin because it needs to be split for filtering. +# This could in theory be done later, without 'cat', but +# it is much easier for others to follow when it's here. +# +cat > "${data}"; + + +#--------------------------------------------------------------- +# preprocessing + +## +# If there is no exclusion file, passthru. +# +if test -f "${LIST}"; then + + ## + # Preprocess user input '$LIST' to include a suffix that + # works better with 'grep'. Write to file for multi-line + # support. The '!' before ' grep' is to ignore a no-match + # error that will otherwise cause the script to exit early. + # + suffix < "${LIST}" > "${user}"; + ! grep -f "${user}" "${data}" \ + | awk '{print $1}' \ + | suffix \ + | grep / `# ensure all lines of form: REPO/PACKAGE` \ + > "${real}" \ + ; + exclude="grep -vf ${real} ${data}"; +else + exclude="cat ${data}"; +fi + +#--------------------------------------------------------------- +# filtering + +## +# Enumerate digraph nodes based on (possibly) filtered input. +# +# Pipe to 'tsort' for the final build plan. +# +${exclude} \ + | awk '{ for (f=1;f<=NF;f++) { print $(f),$1 } }' \ + | "${HERE}"/tsort \ + ; + +#--------------------------------------------------------------- +# cleanup + +rm -f "${data}" "${user}" "${real}"; |