tg.sh

   1 #!/bin/sh
   2 # TopGit - A different patch queue manager
   3 # (c) Petr Baudis <pasky@suse.cz>  2008
   4 # GPLv2
   5
   6
   7 ## Auxiliary functions
   8
   9 info()
  10 {
  11         echo "${TG_RECURSIVE}tg: $*"
  12 }
  13
  14 die()
  15 {
  16         info "fatal: $*"
  17         exit 1
  18 }
  19
  20 # setup_hook NAME
  21 setup_hook()
  22 {
  23         hook_call="\"\$(tg --hooks-path)\"/$1 \"\$@\""
  24         if [ -x "$git_dir/hooks/$1" ]; then
  25                 if fgrep -q "$hook_call" "$git_dir/hooks/$1"; then
  26                         # Another job well done!
  27                         return
  28                 fi
  29         fi
  30         # Prepare incanation
  31         if [ -x "$git_dir/hooks/$1" ]; then
  32                 hook_call="$hook_call"' || exit $?'
  33         else
  34                 hook_call="exec $hook_call"
  35         fi
  36         # Insert call into the hook
  37         {
  38                 echo "#!/bin/sh"
  39                 echo "$hook_call"
  40                 [ -x "$git_dir/hooks/$1" ] && cat "$git_dir/hooks/$1"
  41         } >"$git_dir/hooks/$1+"
  42         chmod a+x "$git_dir/hooks/$1+"
  43         mv "$git_dir/hooks/$1+" "$git_dir/hooks/$1"
  44 }
  45
  46 # setup_ours (no arguments)
  47 setup_ours()
  48 {
  49         if [ ! -s "$git_dir/info/gitattributes" ] || ! grep -q topmsg "$git_dir/info/gitattributes"; then
  50                 {
  51                         echo -e ".topmsg\tmerge=ours"
  52                         echo -e ".topdeps\tmerge=ours"
  53                 } >>"$git_dir/info/gitattributes"
  54         fi
  55         if ! git config merge.ours.driver >/dev/null; then
  56                 git config merge.ours.name '"always keep ours" merge driver'
  57                 git config merge.ours.driver 'touch %A'
  58         fi
  59 }
  60
  61 # measure_branch NAME [BASE]
  62 measure_branch()
  63 {
  64         _name="$1"; _base="$2"
  65         [ -n "$_base" ] || _base="refs/top-bases/$_name"
  66         # The caller should've verified $name is valid
  67         _commits="$(git rev-list "$_name" ^"$_base" | wc -l)"
  68         _nmcommits="$(git rev-list --no-merges "$_name" ^"$_base" | wc -l)"
  69         if [ $_commits -gt 1 ]; then
  70                 _suffix="commits"
  71         else
  72                 _suffix="commit"
  73         fi
  74         echo "$_commits/$_nmcommits $_suffix"
  75 }
  76
  77 # branch_contains B1 B2
  78 # Whether B1 is a superset of B2.
  79 branch_contains()
  80 {
  81         [ -z "$(git rev-list ^"$1" "$2")" ]
  82 }
  83
  84 # needs_update NAME [BRANCHPATH...]
  85 # This function is recursive; it outputs reverse path from NAME
  86 # to the branch (e.g. B_DIRTY B1 B2 NAME), one path per line,
  87 # inner paths first. Innermost name can be ':' if the head is
  88 # not in sync with the base.
  89 needs_update()
  90 {
  91         {
  92         git cat-file blob "$1:.topdeps" 2>/dev/null |
  93                 while read _dep; do
  94                         _dep_is_tgish=1
  95                         git rev-parse --verify "refs/top-bases/$_dep" >/dev/null 2>&1 ||
  96                                 _dep_is_tgish=
  97
  98                         # Shoo shoo, keep our environment alone!
  99                         [ -z "$_dep_is_tgish" ] || (needs_update "$_dep" "$@")
 100
 101                         _dep_base_uptodate=1
 102                         if [ -n "$_dep_is_tgish" ]; then
 103                                 branch_contains "$_dep" "refs/top-bases/$_dep" || _dep_base_uptodate=
 104                         fi
 105
 106                         if [ -z "$_dep_base_uptodate" ]; then
 107                                 # _dep needs to be synced with its base
 108                                 echo ": $_dep $*"
 109                         elif ! branch_contains "refs/top-bases/$1" "$_dep"; then
 110                                 # Some new commits in _dep
 111                                 echo "$_dep $*"
 112                         fi
 113                 done
 114         } || : # $1 is not tracked by TopGit anymore
 115 }
 116
 117 # branch_empty NAME
 118 branch_empty()
 119 {
 120         [ -z "$(git diff-tree "refs/top-bases/$1" "$1" | fgrep -v "     .top")" ]
 121 }
 122
 123 # switch_to_base NAME [SEED]
 124 switch_to_base()
 125 {
 126         _base="refs/top-bases/$1"; _seed="$2"
 127         # We have to do all the hard work ourselves :/
 128         # This is like git checkout -b "$_base" "$_seed"
 129         # (or just git checkout "$_base"),
 130         # but does not create a detached HEAD.
 131         git read-tree -u -m HEAD "${_seed:-$_base}"
 132         [ -z "$_seed" ] || git update-ref "$_base" "$_seed"
 133         git symbolic-ref HEAD "$_base"
 134 }
 135
 136
 137 ## Initial setup
 138
 139 set -e
 140 git_dir="$(git rev-parse --git-dir)"
 141 root_dir="$(git rev-parse --show-cdup)"; root_dir="${root_dir:-.}"
 142 # make sure merging the .top* files will always behave sanely
 143 setup_ours
 144 setup_hook "pre-commit"
 145
 146
 147 ## Dispatch
 148
 149 # We were sourced from another script for our utility functions;
 150 # this is set by hooks.
 151 [ -z "$tg__include" ] || return 0
 152
 153 cmd="$1"
 154 [ -n "$cmd" ] || die "He took a duck in the face at two hundred and fifty knots"
 155 shift
 156
 157 case "$cmd" in
 158 help)
 159         echo "TopGit v0.1 - A different patch queue manager"
 160         echo "Usage: tg (create|delete|info|patch|summary|update|help) ..."
 161         exit 1;;
 162 create|delete|info|patch|summary|update)
 163         . "@cmddir@"/tg-$cmd;;
 164 --hooks-path)
 165         # Internal command
 166         echo "@hooksdir@";;
 167 *)
 168         echo "Unknown subcommand: $cmd" >&2
 169         exit 1;;
 170 esac