Beta stage: traverses through /**/* without error (some files excluded; see test/totest.sh)

rdlink.sh

@@ -18,14 +18,45 @@ LOG_LEVEL="${LOG_LEVEL:-1}" # 7 = debug -> 0 = emergency
 
 rl::rdlink() {
   local subject=
+  local work=
+  local resolved=0
 
   info "pwd: $(pwd)"
   info "Processing... $@"
 
   subject="$(rl::normalize "${1:-}")" || true
   # Follow multiple symlinks
-  while subject="$(rl::quicklink "${subject}")" ; do : ; done
-  subject="$(rl::canon "${subject}")" || true
+  while subject="$(rl::quicklink "${subject}")" ; do
+    # A link was resolved at least once
+    info "rl::rdlink - Link found: $subject"
+    resolved=1
+  done
+
+  # Special cases handling
+  {
+    # If subject is still a link, after rl::quicklink call(s)
+    # current user has no permission to access the link itself
+    # (e.g. /proc/**/cwd)
+    if [ -L "${subject}" ] ; then
+      info "rl::rdlink exit - can't access link ${subject}"
+      printf "\n"
+      return 1
+    fi
+  }
+
+  # Empty output if (dirname $subject) is not a valid path
+  if ! work="$(rl::canon "${subject}")" ; then
+    # Special: Links resolved to something like: /proc/2267178/fd/pipe:[22306727]
+    # are not existing files but `readlink -f` prints result anyway
+    # Printing result if a link was resolved at least once
+    if (( ! resolved )); then
+      info "rl::rdlink exit - invalid path ${subject}"
+      printf "\n"
+      return 1
+    fi
+  else
+    subject="${work}"
+  fi
 
   printf "${subject}\n"
 }
@@ -43,13 +74,13 @@ rl::quicklink() {
   fi
   info " - symlink ${1} -> ${subject}"
 
-  # relative target; append root
+  # relative symlink target; prepend its parent direcotry
   if [[ "${subject}" != "/"* ]]; then
     work="$(rl::canon "$(dirname -- "${1:-}")")"
     subject="${work}/${subject}"
     info " - relative link resolved: ${subject}"
   fi
-  
+
   printf "${subject}\n"
   return 0
 }
@@ -61,23 +92,40 @@ rl::canon() {
 
   info "Canonicalize path... ${1:-}"
   if work="$(cd "${1:-}" >/dev/null 2>&1 && pwd -P)" ; then
-    subject="${work}"
+    # Special: `pwd -P` returns with // as root for links starting at /
+    # e.g. $(readlink /proc/self/root) == "/"
+    #      $(cd /proc/self/root/mnt && pwd -P) == "//mnt"
+    subject="$(rl::normalize "${work}")"
     info " - directory: ${subject}"
   elif work="$(cd "$(dirname -- "${1:-}")" >/dev/null 2>&1 && pwd -P)" ; then
     bname="$(basename -- "${1:-}")"
+
+    # Special: / produces //
+    [[ "${work}" == "/" ]] && work=
+
     subject="${work}${bname:+"/${bname}"}"
     info " - parent: ${subject}"
   else
-    info " - no hit"
+    info " - no hit for: ${1:-}"
     subject="${1:-}"
+    return 1
   fi
 
-  printf "${subject}\n"
+  printf -- "${subject}\n"
+  return 0
 }
 
 rl::normalize() {
+  local work=
   info "Normalizing... ${1:-}"
-  printf -- "${1:-}\n"
+
+  work="${1:-}"
+  # Remove multiple /
+  while [[ "${work:-}" = *"//"* ]]; do
+    work="${work//'//'/'/'}"
+  done
+
+  printf -- "${work}\n"
 }
 
 rl::main() {
@@ -118,20 +166,20 @@ function rl::log () {
     printf "%s [%9s] %s\n" "$(date -u +"%Y-%m-%d %H:%M:%S UTC")" "${log_level}" "${log_line}" 1>&2
   done <<< "${@:-}"
 }
-emergency () {                                  rl::log emergency "${@}"; exit 1; }
-alarm()      { [[ "${LOG_LEVEL:-0}" -ge 1 ]] && rl::log alert "${@}"; true; }
-critical ()  { [[ "${LOG_LEVEL:-0}" -ge 2 ]] && rl::log critical "${@}"; true; }
-error ()     { [[ "${LOG_LEVEL:-0}" -ge 3 ]] && rl::log error "${@}"; true; }
-warning ()   { [[ "${LOG_LEVEL:-0}" -ge 4 ]] && rl::log warning "${@}"; true; }
-notice ()    { [[ "${LOG_LEVEL:-0}" -ge 5 ]] && rl::log notice "${@}"; true; }
-info ()      { [[ "${LOG_LEVEL:-0}" -ge 6 ]] && rl::log info "${@}"; true; }
-debug ()     { [[ "${LOG_LEVEL:-0}" -ge 7 ]] && rl::log debug "${@}"; true; }
-msg ()       {                                  echo "$@"; true; }
+emergency() {                                  rl::log emergency "${@}"; exit 1; }
+alarm()     { [[ "${LOG_LEVEL:-0}" -ge 1 ]] && rl::log alert "${@}"; true; }
+critical()  { [[ "${LOG_LEVEL:-0}" -ge 2 ]] && rl::log critical "${@}"; true; }
+error()     { [[ "${LOG_LEVEL:-0}" -ge 3 ]] && rl::log error "${@}"; true; }
+warning()   { [[ "${LOG_LEVEL:-0}" -ge 4 ]] && rl::log warning "${@}"; true; }
+notice()    { [[ "${LOG_LEVEL:-0}" -ge 5 ]] && rl::log notice "${@}"; true; }
+info()      { [[ "${LOG_LEVEL:-0}" -ge 6 ]] && rl::log info "${@}"; true; }
+debug()     { [[ "${LOG_LEVEL:-0}" -ge 7 ]] && rl::log debug "${@}"; true; }
+msg()       {                                  echo "$@"; true; }
 
 
 # Provide as function to be called when sourced
 rdlink() {
-  rl::main "$@"
+  rl::rdlink "$@"
 }
 
 ### Check if script is _sourced