Introduce filter_to, pick_fields

diff --git a/git-remote-gcrypt b/git-remote-gcrypt
index 8dfa4c7e78f71f5d0921b8a3539d67b7d1d07971..33a5d20982597d0969dbe2dc7923ec07213a66ed 100755 (executable)
--- a/git-remote-gcrypt
+++ b/git-remote-gcrypt
@@ -19,6 +19,9 @@ Packkey_bytes=33  # 33 random bytes for passphrase, still compatible if changed
 Hashtype=SHA256   # SHA512 SHA384 SHA256 SHA224 supported.
 Packpat="pack :*:"
 Manifestfile=91bd0c092128cf2e60e1a608c31e92caf1f9c1595f83f2890ef17c0e4881aa0a
+Hex40="[a-f0-9]"
+Hex40=$Hex40$Hex40$Hex40$Hex40$Hex40$Hex40$Hex40$Hex40
+Hex40=$Hex40$Hex40$Hex40$Hex40$Hex40 # Match SHA-1 hexdigest
 
 Did_find_repo=  # yes for connected, no for no repo
 Repoid=
@@ -61,9 +64,11 @@ tac() { sed '1!G;h;$!d'; }
 
 # setvar is used for named return variables
 # $1 *must* be a valid variable name, $2 is any value
+# our convention: variable name requires @ prefix
 setvar()
 {
-       eval $1=\$2
+       isnull "${1##@*}" || echo_die "Missing @ for return variable: $1"
+       eval ${1#@}=\$2
 }
 
 Newline="
@@ -72,10 +77,10 @@ Newline="
 # $1 is return var, $2 is value appended with newline separator
 append_to()
 {
-       local tmp_=
-       eval tmp_=\$$1
-       isnull "$tmp_" || tmp_=$tmp_$Newline
-       setvar "$1" "$tmp_$2"
+       local append_tmp_=
+       eval append_tmp_=\$${1#@}
+       isnull "$append_tmp_" || append_tmp_=$append_tmp_$Newline
+       setvar "$1" "$append_tmp_$2"
 }
 
 # Split $1 into $2:$3
@@ -85,6 +90,52 @@ splitcolon()
        setvar "$3" "${1#*:}"
 }
 
+# if $1 contains $2
+contains()
+{
+       isnull "${1##*"$2"*}"
+}
+
+# Pick words from each line
+# $1 return variable name
+# $2 field list "1,2,3"
+# $3 input value
+pick_fields()
+{
+       local f_line_= f_result_= f_mask_= f_ret_var= f_oifs="$IFS" IFS=
+       f_ret_var=$1
+       f_mask_=$2
+       IFS=$Newline
+       for f_line_ in $3
+       do
+               IFS=$f_oifs
+               # split $f_line_ into words and pick them out
+               set -- $f_line_
+               f_line_=
+               ! contains "$f_mask_" 1 || f_line_=${1:-}
+               ! contains "$f_mask_" 2 || f_line_="$f_line_ ${2:-}"
+               ! contains "$f_mask_" 3 || f_line_="$f_line_ ${3:-}"
+               append_to @f_result_ "${f_line_# }"
+       done
+       setvar "$f_ret_var" "$f_result_"
+}
+
+# Take all lines matching $2 (anchored front)
+# $1 return variable name
+# $2 filter word
+# $3 input value
+filter_to()
+{
+       local f_line= f_result_= IFS=
+       IFS=$Newline
+       for f_line in $3
+       do
+               iseq "$f_line" "${f_line#$2}" || append_to @f_result_ "$f_line"
+       done
+       setvar "$1" "$f_result_"
+}
+
+
 ## gitception part
 # Fetch giturl $1, file $2
 gitception_get()
@@ -371,7 +422,7 @@ read_config()
 
                isnonnull "$keyid_" &&
                signers_="$signers_ $keyid_" &&
-               append_to good_sig "^\[GNUPG:\] GOODSIG $keyid_" || {
+               append_to @good_sig "^\[GNUPG:\] GOODSIG $keyid_" || {
                        echo_info "WARNING: Skipping missing key $recp_"
                        continue
                }
@@ -401,7 +452,7 @@ ensure_connected()
                return
        fi
        Did_find_repo=no
-       read_config sig_match signer_text
+       read_config @sig_match @signer_text
 
        iseq "${NAME#gcrypt::}" "$URL" || r_name=$NAME
 
@@ -465,11 +516,11 @@ ensure_connected()
                echo_die "Failed to decrypt manifest!"
        rm -f "$TmpManifest_Enc"
 
-       Branchlist=$(xecho "$manifest_" | xgrep -E '^[0-9a-f]{40} ')
-       Packlist=$(xecho "$manifest_" | xgrep "^pack ")
-       Keeplist=$(xecho "$manifest_" | xgrep "^keep ")
-       Extension_list=$(xecho "$manifest_" | xgrep "^extn ")
-       rcv_repoid=$(xecho "$manifest_" | xgrep "^repo ")
+       filter_to @Packlist "pack " "$manifest_"
+       filter_to @Keeplist "keep " "$manifest_"
+       filter_to @Extension_list "extn " "$manifest_"
+       filter_to @rcv_repoid "repo " "$manifest_"
+       filter_to @Branchlist "$Hex40 " "$manifest_"
 
        rcv_repoid=${rcv_repoid#repo }
        rcv_repoid=${rcv_repoid% *}
@@ -496,7 +547,7 @@ ensure_connected()
 fetch_decrypt_pack()
 {
        local key_= rcv_id= htype_= pack_= hfunc_=
-       splitcolon "${1#pack :}" htype_ pack_
+       splitcolon "${1#pack :}" @htype_ @pack_
 
        if isnoteq "$htype_" SHA256 && isnoteq "$htype_" SHA224 &&
                isnoteq "$htype_" SHA384 && isnoteq "$htype_" SHA512
@@ -507,7 +558,8 @@ fetch_decrypt_pack()
        rcv_id=$(gpg_hash "$htype_" < "$TmpPack_Encrypted") &&
        iseq "$rcv_id" "$pack_" ||
                echo_die "Packfile $pack_ does not match digest!"
-       key_=$(xecho "$Packlist" | grep "$pack_" | cut -f 3 -d ' ')
+       filter_to @key_ "pack :${htype_}:$pack_" "$Packlist"
+       pick_fields @key_ 3 "$key_"
        DECRYPT "$key_" < "$TmpPack_Encrypted"
 }
 
@@ -529,8 +581,8 @@ repack_if_needed()
                Repack_limit=1
        fi
 
-       premote_=$(xecho "$Packlist" | cut -f 1-2 -d ' ')
-       pkeep_=$(xecho "$Keeplist" | cut -f 2 -d ' ')
+       pick_fields @premote_ 1,2 "$Packlist"
+       pick_fields @pkeep_ 2 "$Keeplist"
 
        if isnull "$pkeep_"; then
                n_=$(xecho "$Packlist" | wc -l)
@@ -576,8 +628,8 @@ repack_if_needed()
        fi
 
        pack_id=$(pack_hash < "$TmpPack_Encrypted")
-       append_to Packlist "pack :${Hashtype}:$pack_id $key_"
-       append_to Keeplist "keep :${Hashtype}:$pack_id 1"
+       append_to @Packlist "pack :${Hashtype}:$pack_id $key_"
+       append_to @Keeplist "keep :${Hashtype}:$pack_id 1"
        rm -r -f "$Localdir/pack"
        setvar "$3" yes
 }
@@ -628,7 +680,7 @@ do_fetch()
        TmpPack_Encrypted="$Localdir/tmp_pack_ENCRYPTED_.$$"
 
        # The `+` for $GITCEPTION is pointless but we will be safe for stacking
-       premote_=$(xecho "$Packlist" | cut -f 1-2 -d ' ')
+       pick_fields @premote_ 1,2 "$Packlist"
        if [ -s "$Localdir/have_packs+" ]
        then
                pneed_="$(xecho "$premote_" | xgrep -v -x -f "$Localdir/have_packs+")"
@@ -677,15 +729,15 @@ do_push()
        while read line_ # from <<
        do
                # +src:dst -- remove leading + then split at :
-               splitcolon "${line_#+}" src_ dst_
+               splitcolon "${line_#+}" @src_ @dst_
                if isnonnull "$src_"
                then
-                       append_to rev_list "$src_"
+                       append_to @rev_list "$src_"
                        obj_=$(xecho "$src_" | safe_git_rev_parse)
                else
                        obj_=$del_hash  # Mark for deletion
                fi
-               append_to Branchlist "$obj_ $dst_"
+               append_to @Branchlist "$obj_ $dst_"
        done <<EOF
 $1
 EOF
@@ -704,11 +756,11 @@ EOF
        if [ -s "$TmpObjlist" ]
        then
                pack_id=$(pack_hash < "$TmpPack_Encrypted")
-               repack_if_needed "$pack_id" "$key_" did_repack pack_delete
+               repack_if_needed "$pack_id" "$key_" @did_repack @pack_delete
 
                if isnoteq "$did_repack" yes
                then
-                       append_to Packlist "pack :${Hashtype}:$pack_id $key_"
+                       append_to @Packlist "pack :${Hashtype}:$pack_id $key_"
                fi
                # else, repack rewrote Packlist
 
@@ -757,7 +809,7 @@ EOF
        xecho "$1" | while read line_
        do
                # +src:dst -- remove leading + then split at :
-               splitcolon "${line_#+}" src_ dst_
+               splitcolon "${line_#+}" @src_ @dst_
                echo_git "ok $dst_"
        done
        
@@ -812,7 +864,7 @@ gcrypt_main_loop()
                        do
                                case "$input_inner" in
                                push\ *)
-                                       append_to args_ "${input_inner#push }"
+                                       append_to @args_ "${input_inner#push }"
                                ;;
                                *)
                                        break