PATCH: Allow tree-id to return the ID of a tree object

While playing with cg-ls, I tried:

Patch attached.

Index: commit-id
===================================================================
--- 6ad600e20c89323c1d3049f75b8ca9b0a2d72167/commit-id  (mode:100755 sha1:4efcb6bdfdb2b2c5744f5d4d47d92beb7777ed59)
+++ uncommitted/commit-id  (mode:100775)
@@ -9,22 +9,30 @@
 SHA1ONLY="^$SHA1$"
 
 id=$1
+
 if [ ! "$id" ] || [ "$id" = "this" ] || [ "$id" = "HEAD" ]; then
 	id=$(cat .git/HEAD)
-fi
 
-if (echo $id | egrep -vq "$SHA1ONLY") && [ -r ".git/refs/tags/$id" ]; then
+elif [ -r ".git/refs/tags/$id" ]; then
 	id=$(cat ".git/refs/tags/$id")
-fi
 
-if (echo $id | egrep -vq "$SHA1ONLY") && [ -r ".git/refs/heads/$id" ]; then
+elif [ -r ".git/refs/heads/$id" ]; then
 	id=$(cat ".git/refs/heads/$id")
-fi
 
-idpref=$(echo "$id" | cut -c -2)
-idpost=$(echo "$id" | cut -c 3-)
-if [ $(find ".git/objects/$idpref" -name "$idpost*" 2>/dev/null | wc -l) -eq 1 ]; then
-	id=$idpref$(basename $(echo .git/objects/$idpref/$idpost*))
+# Short id's must be lower case and at least 4 digits.
+elif [[ "$id" == [0-9a-z][0-9a-z][0-9a-z][0-9a-z]* ]]; then
+	idpost=${id#??}
+	idpref=${id%$idpost}
+
+	# Assign array elements to matching names
+	idmatch=($(echo .git/objects/$idpref/$idpost*))
+
+	if [ ${#idmatch[*]} -eq 1 ] && [ -r "$idmatch" ]; then
+		id=$idpref${idmatch#.git/objects/$idpref/}
+	elif [ ${#idmatch[*]} -gt 1 ]; then
+		echo "Ambiguous id: $id" >&2
+		exit 1
+	fi
 fi
 
 if echo $id | egrep -vq "$SHA1ONLY"; then
Index: tree-id
===================================================================
--- 6ad600e20c89323c1d3049f75b8ca9b0a2d72167/tree-id  (mode:100755 sha1:1495ff78af71b57e21653512932bcda88fe05454)
+++ uncommitted/tree-id  (mode:100775)
@@ -7,8 +7,35 @@
 
 SHA1="[A-Za-z0-9]{40}"
 TREE="^tree $SHA1$"
+SHA1ONLY="^$SHA1$"
 
-id=$(cat-file commit $(commit-id "$1") | egrep "$TREE" | cut -d ' ' -f 2)
+id=$1
+
+# Is it a commit?
+commit=$(commit-id $id 2>/dev/null)
+if [ "$commit" ]; then
+	id=$(cat-file commit "$commit") | egrep "$TREE" | cut -d ' ' -f 2)
+
+# Short id's must be lower case and at least 4 digits.
+elif [[ "$id" == [0-9a-z][0-9a-z][0-9a-z][0-9a-z]* ]]; then
+	idpost=${id#??}
+	idpref=${id%$idpost}
+
+	# Assign array elements to matching names
+	idmatch=($(echo .git/objects/$idpref/$idpost*))
+
+	if [ ${#idmatch[*]} -eq 1 ] && [ -r "$idmatch" ]; then
+		id=$idpref${idmatch#.git/objects/$idpref/}
+	elif [ ${#idmatch[*]} -gt 1 ]; then
+		echo "Ambiguous id: $id" >&2
+		exit 1
+	fi
+fi
+
+if echo $id | egrep -vq "$SHA1ONLY"; then
+	echo "Invalid id: $id" >&2
+	exit 1
+fi
 
 if [ "$(cat-file -t "$id")" != "tree" ]; then
 	echo "Invalid id: $id" >&2
Index: parent-id
===================================================================
--- 6ad600e20c89323c1d3049f75b8ca9b0a2d72167/parent-id  (mode:100755 sha1:f35877a6aa5b68d2fb4a388dcfa9b3e64262604e)
+++ uncommitted/parent-id  (mode:100775)
@@ -5,7 +5,8 @@
 #
 # Takes ID of the current commit, defaults to HEAD.
 
-PARENT="^parent [A-Za-z0-9]{40}$"
+SHA1="[A-Za-z0-9]{40}"
+PARENT="^parent $SHA1$"
 
 id=$(commit-id $1) || exit 1
 

Petr Baudis· Apr 27, 2005, 23:22 UTC · re: Philip Pokorny · lore

Re: PATCH: Allow tree-id to return the ID of a tree object

> While playing with cg-ls, I tried:
> 
> % cg-ls
> ... snip ...
> 100644  blob    bc607fd55f6ce4e56ce87766369b5d4d55ec79af        object.h
> 100755  blob    f35877a6aa5b68d2fb4a388dcfa9b3e64262604e        parent-id
> 040000  tree    bfb75011c32589b282dd9c86621dadb0f0bb3866        ppc
> 100644  blob    d922305ee0f5583bdfcb629f6d4061e11e0fa859        read-cache.c
> 100644  blob    1ad7ffc555b635fe57fa7834b12d71ff576be065        read-tree.c
> ... snip ...
> % cg-ls bfb75011c32589b282dd9c86621dadb0f0bb3866       <-- the ppc tree ID
> Invalid id: bfb75011c32589b282dd9c86621dadb0f0bb3866
> usage: cat-file [-t | tagname] <sha1>
> usage: cat-file [-t | tagname] <sha1>
> Invalid id:
> 
> 
> Shouldn't cg-ls give a listing of a sub-tree?  The cg-help says it takes
> a TREE-ID?
> 
> The problem seems to be that tree-id really only accepts a commit-id and
> returns the TREE-ID of that commit.
> 
> So I modified commit-id, tree-id and parent-id to make them more similar
> in coding style, force "short-id" names to be at least 4 lower case
> letters, and have tree-id accept short, unambiguous ID's and bare SHA1-ID's.
> 
> Patch attached.

Could you please functionally split and sign off your patch?

-- 
				Petr "Pasky" Baudis
Stuff: http://pasky.or.cz/
C++: an octopus made by nailing extra legs onto a dog. -- Steve Taylor

Re: PATCH[0/4]: Allow tree-id to return the ID of a tree object

Petr Baudis wrote:

>Could you please functionally split and sign off your patch?
>  
>

Apologies, I'm still a bit new to LKML etiquette...

>Also, I'd prefer not to have the sha1 completion logic duplicated; what
>about just having commit-id take a parameter not to validate its id?
>Actually, that's ugly too. I think the cleanest solution would be to
>reintroduce the cg-Xnormid, now to only really do the _common_ stuff -
>basically everything up to the typecheck (exclusively) in commit-id.
>  
>

Re: PATCH[1/4]: Allow tree-id to return the ID of a tree object

Patch to re-introduce cg-Xnormid for common ID normalizing.

Signed-off-by: Philip Pokorny <ppokorny@mindspring.com>

Index: cg-Xnormid
===================================================================
--- /dev/null  (tree:6ad600e20c89323c1d3049f75b8ca9b0a2d72167)
+++ uncommitted/cg-Xnormid  (mode:100755 sha1:6dc089c8d571f330e2e01d96f79616d6146840ee)
@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+#
+# Normalize an ID to an SHA1 hash value
+#    Strings resolve in order:
+#       NULL, this, HEAD  => .git/HEAD
+#       <tags>
+#       <heads>
+#       short SHA1 (4 or more hex digits)
+#
+# Copyright (c) Philip Pokorny, 2005
+
+id="$1"
+
+if [ ! "$id" ] || [ "$id" = "this" ] || [ "$id" = "HEAD" ]; then
+	read id < .git/HEAD
+
+elif [ -r ".git/refs/tags/$id" ]; then
+	read id < ".git/refs/tags/$id"
+
+elif [ -r ".git/refs/heads/$id" ]; then
+	read id < ".git/refs/heads/$id"
+
+# Short id's must be lower case and at least 4 digits.
+elif [[ "$id" == [0-9a-z][0-9a-z][0-9a-z][0-9a-z]* ]]; then
+	idpost=${id#??}
+	idpref=${id%$idpost}
+
+	# Assign array elements to matching names
+	idmatch=(.git/objects/$idpref/$idpost*)
+
+	if [ ${#idmatch[*]} -eq 1 ] && [ -r "$idmatch" ]; then
+		id=$idpref${idmatch#.git/objects/$idpref/}
+	elif [ ${#idmatch[*]} -gt 1 ]; then
+		echo "Ambiguous id: $id" >&2
+		exit 1
+	fi
+fi
+
+# FIXME? Should we verify the existance of the ID in the object cache?
+
+# If we don't have a 40-char ID by now, it's an error
+if [ ${#id} -ne 40 ]; then
+	echo "Invalid id: $id" >&2
+	exit 1
+fi
+
+echo $id
Index: Makefile
===================================================================
--- 6ad600e20c89323c1d3049f75b8ca9b0a2d72167/Makefile  (mode:100644 sha1:d73bea1cbb9451a89b03d6066bf2ed7fec32fd31)
+++ uncommitted/Makefile  (mode:100664)
@@ -44,7 +44,7 @@
 	cg-add cg-admin-lsobj cg-cancel cg-clone cg-commit cg-diff \
 	cg-export cg-help cg-init cg-log cg-ls cg-merge cg-mkpatch \
 	cg-patch cg-pull cg-branch-add cg-branch-ls cg-rm cg-seek cg-status \
-	cg-tag cg-update cg-Xlib
+	cg-tag cg-update cg-Xlib cg-Xnormid
 
 COMMON=	read-cache.o
 

Re: PATCH[2/4]: Allow tree-id to return the ID of a tree object

Convert commit-id to use the new cg-Xnormid internal script

Signed-off-by: Philip Pokorny <ppokorny@mindspring.com>

Index: commit-id
===================================================================
--- 6ad600e20c89323c1d3049f75b8ca9b0a2d72167/commit-id  (mode:100755 sha1:4efcb6bdfdb2b2c5744f5d4d47d92beb7777ed59)
+++ uncommitted/commit-id  (mode:100775)
@@ -1,39 +1,25 @@
 #!/usr/bin/env bash
 #
 # Get ID of commit associated with given id or HEAD.
+#
 # Copyright (c) Petr Baudis, 2005
 #
-# Takes the appropriate ID, defaults to HEAD.
-
-SHA1="[A-Za-z0-9]{40}"
-SHA1ONLY="^$SHA1$"
-
-id=$1
-if [ ! "$id" ] || [ "$id" = "this" ] || [ "$id" = "HEAD" ]; then
-	id=$(cat .git/HEAD)
-fi
 
-if (echo $id | egrep -vq "$SHA1ONLY") && [ -r ".git/refs/tags/$id" ]; then
-	id=$(cat ".git/refs/tags/$id")
-fi
-
-if (echo $id | egrep -vq "$SHA1ONLY") && [ -r ".git/refs/heads/$id" ]; then
-	id=$(cat ".git/refs/heads/$id")
-fi
+# Save for later error message
+orig="$1"
 
-idpref=$(echo "$id" | cut -c -2)
-idpost=$(echo "$id" | cut -c 3-)
-if [ $(find ".git/objects/$idpref" -name "$idpost*" 2>/dev/null | wc -l) -eq 1 ]; then
-	id=$idpref$(basename $(echo .git/objects/$idpref/$idpost*))
-fi
+# Normalize to SHA1 form
+id=$(cg-Xnormid "$orig")
 
-if echo $id | egrep -vq "$SHA1ONLY"; then
-	echo "Invalid id: $id" >&2
+if [ ! "$id" ]; then
+	# cg-Xnormid already reported the error
 	exit 1
 fi
 
-if [ "$(cat-file -t "$id")" != "commit" ]; then
-	echo "Invalid id: $id" >&2
+# cat-file will verify that $id is a valid SHA1 ID for us
+# If it isn't, we'll get '' back
+if [ "$(cat-file -t "$id" 2>/dev/null)" != "commit" ]; then
+	echo "Invalid commit id: $orig" >&2
 	exit 1
 fi
 

Re: PATCH[2/4]: Allow tree-id to return the ID of a tree object

Philip Pokorny wrote:

> Convert commit-id to use the new cg-Xnormid internal script
>
> Signed-off-by: Philip Pokorny <ppokorny@mindspring.com>

But then again, I seem to be having trouble getting my git working 
directory to track or match the current head.  That would be:
    49612c471eebd26efe926a71752e254c1cdc382d
right?

:v)

Re: PATCH[3/4]: Allow tree-id to return the ID of a tree object

Convert tree-id to use cg-Xnormid to normalize an ID

Signed-off-by: Philip Pokorny <ppokorny@mindspring.com>

Index: tree-id
===================================================================
--- 6ad600e20c89323c1d3049f75b8ca9b0a2d72167/tree-id  (mode:100755 sha1:1495ff78af71b57e21653512932bcda88fe05454)
+++ uncommitted/tree-id  (mode:100775)
@@ -1,17 +1,31 @@
 #!/usr/bin/env bash
 #
 # Get ID of tree associated with given commit or HEAD.
+#
 # Copyright (c) Petr Baudis, 2005
 #
-# Takes ID of the appropriate commit, defaults to HEAD.
 
-SHA1="[A-Za-z0-9]{40}"
-TREE="^tree $SHA1$"
+# Save for later error message
+orig="$1"
 
-id=$(cat-file commit $(commit-id "$1") | egrep "$TREE" | cut -d ' ' -f 2)
+# Normalize to SHA1 form
+id=$(cg-Xnormid "$1")
+if [ ! "$id" ]; then
+	# cg-Xnormid already reported the error
+	exit 1
+fi
+
+# Is it a commit?
+idtype=$(cat-file -t $id 2>/dev/null)
+if [ "$idtype" = "commit" ]; then
+	# Get the tree
+	id=$(cat-file commit "$id" | sed -e 's/tree //;q')
+fi
 
-if [ "$(cat-file -t "$id")" != "tree" ]; then
-	echo "Invalid id: $id" >&2
+# cat-file will verify that $id is a valid SHA1 ID for us
+# If it isn't, we'll get '' back
+if [ "$(cat-file -t "$id" 2>/dev/null)" != "tree" ]; then
+	echo "Invalid tree id: $orig" >&2
 	exit 1
 fi
 

Re: PATCH[4/4]: Allow tree-id to return the ID of a tree object

NOTE: parent-id uses commit-id rather than cg-Xnormid directly

Signed-off-by: Philip Pokorny <ppokorny@mindspring.com>

Index: parent-id
===================================================================
--- 6ad600e20c89323c1d3049f75b8ca9b0a2d72167/parent-id  (mode:100755 sha1:f35877a6aa5b68d2fb4a388dcfa9b3e64262604e)
+++ uncommitted/parent-id  (mode:100775)
@@ -1,12 +1,19 @@
 #!/usr/bin/env bash
 #
 # Get ID of parent commit to a given revision or HEAD.
+# NOTE: will return multiple SHA1s if ID is a commit with multiple parents
+#
 # Copyright (c) Petr Baudis, 2005
 #
-# Takes ID of the current commit, defaults to HEAD.
 
-PARENT="^parent [A-Za-z0-9]{40}$"
+# Save for later error message
+orig="$1"
 
-id=$(commit-id $1) || exit 1
+# Normalize to SHA1 form and verify its a commit
+id=$(commit-id "$1")
+if [ ! "$id" ]; then
+	# commit-id already reported the error
+	exit 1
+fi
 
-cat-file commit $id | egrep "$PARENT" | cut -d ' ' -f 2
+cat-file commit $id | awk '/^parent/{print $2};/^$/{exit}'