nixpkgs/pkgs/build-support/setup-hooks/set-source-date-epoch-to-latest.sh
Robin Gloster 34faed5bb0
set-source-date-epoch-to-latest: fix warning
If there was no older file than $NIX_BUILD_TOP this would result in a
warning, e.g. with nix-info.

```
/nix/store/15kgcm8hnd99p7plqzx7p4lcr2jni4df-set-source-date-epoch-to-latest.sh: line 13: [: : integer expression expected
```
2018-11-29 09:49:08 +01:00

35 lines
1.3 KiB
Bash

updateSourceDateEpoch() {
local path="$1"
# Get the last modification time of all regular files, sort them,
# and get the most recent. Maybe we should use
# https://github.com/0-wiz-0/findnewest here.
local -a res=($(find "$path" -type f -not -newer "$NIX_BUILD_TOP/.." -printf '%T@ %p\0' \
| sort -n --zero-terminated | tail -n1 --zero-terminated | head -c -1))
local time="${res[0]//\.[0-9]*/}" # remove the fraction part
local newestFile="${res[1]}"
# Update $SOURCE_DATE_EPOCH if the most recent file we found is newer.
if [ "${time:-0}" -gt "$SOURCE_DATE_EPOCH" ]; then
echo "setting SOURCE_DATE_EPOCH to timestamp $time of file $newestFile"
export SOURCE_DATE_EPOCH="$time"
# Warn if the new timestamp is too close to the present. This
# may indicate that we were being applied to a file generated
# during the build, or that an unpacker didn't restore
# timestamps properly.
local now="$(date +%s)"
if [ "$time" -gt $((now - 60)) ]; then
echo "warning: file $newestFile may be generated; SOURCE_DATE_EPOCH may be non-deterministic"
fi
fi
}
postUnpackHooks+=(_updateSourceDateEpochFromSourceRoot)
_updateSourceDateEpochFromSourceRoot() {
if [ -n "$sourceRoot" ]; then
updateSourceDateEpoch "$sourceRoot"
fi
}