kumquat-buildroot/package/pseudo/pseudo-wrapper

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package/pseudo: wrap the real pseudo with a wrapper Running pseudo is more involved than running fakeroot. In the transition from using fakeroot, we just did not account for the extra requirements. First, we explicitly tell pseudo where it is, otherwise it tries to guess. Its guess is correct, but it prints a warning, which is not nice. Second, we tell it where to find the passwd and group files in case it has to emulate access to them. We currently do not use that feature, but better safe than sorry. Third, pseudo spawns a background daemon, and talks to it (when fakeroot would emulate the state all in the current process' state, pseudo uses the daemon to coordinate the state across multiple processes). We are not much interested in the daemon lingering around, so we just tell it to terminate as soon as the last clients quits (this can take up to one second). Fourth and last, pseudo always stores its internal database when exiting, and reloads it when spawned. The database is by default stored in a sub-directory of the prefix it was installed in, but this is impractical for us. We want the database to be specific to the one config dir we are building, so we store the database in a (hidden) sub-dir of the build dir, thus ensuring it is never shared with another build. That directory is hidden (starts with a dot) because we consider that to be our internal state that we do not want to expose to the user. The wrapper has to be relocatable, so we avoid using hard-coded paths in there: we derive those paths fom the runtime path of pseudo. However, the build directory $(BUILD_DIR) is not available in the environment (we do not export it because it conflicts with some buildsystems). Instead, we use $(BASE_DIR) which is exported. Finally, when relocated, the wrapper would not be used in the Buildroot environment, so may not have access to TARGET_DIR or BASE_DIR, unless the user sets them. If he does not, we still want the wrapper to be working (to avoid the warning about the prefix, and to exit the daemon asap); thus we leave the passwd and localstatedir variable alone if we don't have what it needs to set them, rather than set them to incorrect values. Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Gaël PORTAY <gael.portay@savoirfairelinux.com> Cc: Patrick Keroulas <patrick.keroulas@savoirfairelinux.com> Cc: Erico Nunes <nunes.erico@gmail.com> Cc: Julien BOIBESSOT <julien.boibessot@free.fr> Cc: Arnout Vandecappelle <arnout@mind.be> Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2016-11-08 23:18:33 +01:00
#!/bin/sh
if [ "${0##*/}" = "fakeroot" ]; then
cat >&2 <<-_EOF_
WARNING: fakeroot has been replaced with pseudo.
WARNING: Update your script(s) to use pseudo or pseudo-wrapper instead.
_EOF_
fi
package/pseudo: wrap the real pseudo with a wrapper Running pseudo is more involved than running fakeroot. In the transition from using fakeroot, we just did not account for the extra requirements. First, we explicitly tell pseudo where it is, otherwise it tries to guess. Its guess is correct, but it prints a warning, which is not nice. Second, we tell it where to find the passwd and group files in case it has to emulate access to them. We currently do not use that feature, but better safe than sorry. Third, pseudo spawns a background daemon, and talks to it (when fakeroot would emulate the state all in the current process' state, pseudo uses the daemon to coordinate the state across multiple processes). We are not much interested in the daemon lingering around, so we just tell it to terminate as soon as the last clients quits (this can take up to one second). Fourth and last, pseudo always stores its internal database when exiting, and reloads it when spawned. The database is by default stored in a sub-directory of the prefix it was installed in, but this is impractical for us. We want the database to be specific to the one config dir we are building, so we store the database in a (hidden) sub-dir of the build dir, thus ensuring it is never shared with another build. That directory is hidden (starts with a dot) because we consider that to be our internal state that we do not want to expose to the user. The wrapper has to be relocatable, so we avoid using hard-coded paths in there: we derive those paths fom the runtime path of pseudo. However, the build directory $(BUILD_DIR) is not available in the environment (we do not export it because it conflicts with some buildsystems). Instead, we use $(BASE_DIR) which is exported. Finally, when relocated, the wrapper would not be used in the Buildroot environment, so may not have access to TARGET_DIR or BASE_DIR, unless the user sets them. If he does not, we still want the wrapper to be working (to avoid the warning about the prefix, and to exit the daemon asap); thus we leave the passwd and localstatedir variable alone if we don't have what it needs to set them, rather than set them to incorrect values. Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Gaël PORTAY <gael.portay@savoirfairelinux.com> Cc: Patrick Keroulas <patrick.keroulas@savoirfairelinux.com> Cc: Erico Nunes <nunes.erico@gmail.com> Cc: Julien BOIBESSOT <julien.boibessot@free.fr> Cc: Arnout Vandecappelle <arnout@mind.be> Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2016-11-08 23:18:33 +01:00
export PSEUDO_PREFIX="$(dirname "${0%/*}")"
export PSEUDO_OPTS="-t0"
if [ -n "${TARGET_DIR}" ]; then
export PSEUDO_PASSWD="${TARGET_DIR}"
fi
if [ -n "${BASE_DIR}" ]; then
export PSEUDO_LOCALSTATEDIR="${BASE_DIR}/build/.pseudodb"
fi
exec "${0%/*}/pseudo" "${@}"