[PATCH v2 08/14] commit-graph: implement git-commit-graph --clear
Teach Git to delete the current 'graph_head' file and the commit graph it references. This is a good safety valve if somehow the file is corrupted and needs to be recalculated. Since the commit graph is a summary of contents already in the ODB, it can be regenerated. Signed-off-by: Derrick Stolee --- Documentation/git-commit-graph.txt | 16 ++-- builtin/commit-graph.c | 32 +++- t/t5318-commit-graph.sh| 7 ++- 3 files changed, 51 insertions(+), 4 deletions(-) diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt index 99ced16ddc..33d6567f11 100644 --- a/Documentation/git-commit-graph.txt +++ b/Documentation/git-commit-graph.txt @@ -11,6 +11,7 @@ SYNOPSIS [verse] 'git commit-graph' --write [--pack-dir ] 'git commit-graph' --read [--pack-dir ] +'git commit-graph' --clear [--pack-dir ] OPTIONS --- @@ -18,16 +19,21 @@ OPTIONS Use given directory for the location of packfiles, graph-head, and graph files. +--clear:: + Delete the graph-head file and the graph file it references. + (Cannot be combined with --read or --write.) + --read:: Read a graph file given by the graph-head file and output basic - details about the graph file. (Cannot be combined with --write.) + details about the graph file. (Cannot be combined with --clear + or --write.) --graph-id:: When used with --read, consider the graph file graph-.graph. --write:: Write a new graph file to the pack directory. (Cannot be combined - with --read.) + with --clear or --read.) --update-head:: When used with --write, update the graph-head file to point to @@ -61,6 +67,12 @@ $ git commit-graph --write --update-head $ git commit-graph --read --graph-hash= +* Delete /graph-head and the file it references. ++ + +$ git commit-graph --clear --pack-dir= + + GIT --- Part of the linkgit:git[1] suite diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c index d73cbc907d..4970dec133 100644 --- a/builtin/commit-graph.c +++ b/builtin/commit-graph.c @@ -10,6 +10,7 @@ static char const * const builtin_commit_graph_usage[] = { N_("git commit-graph [--pack-dir ]"), + N_("git commit-graph --clear [--pack-dir ]"), N_("git commit-graph --read [--graph-hash=]"), N_("git commit-graph --write [--pack-dir ] [--update-head]"), NULL @@ -17,6 +18,7 @@ static char const * const builtin_commit_graph_usage[] = { static struct opts_commit_graph { const char *pack_dir; + int clear; int read; const char *graph_hash; int write; @@ -25,6 +27,30 @@ static struct opts_commit_graph { struct object_id old_graph_hash; } opts; +static int graph_clear(void) +{ + struct strbuf head_path = STRBUF_INIT; + char *old_path; + + if (!opts.has_existing) + return 0; + + strbuf_addstr(&head_path, opts.pack_dir); + strbuf_addstr(&head_path, "/"); + strbuf_addstr(&head_path, "graph-head"); + if (remove_path(head_path.buf)) + die("failed to remove path %s", head_path.buf); + strbuf_release(&head_path); + + old_path = get_commit_graph_filename_hash(opts.pack_dir, + &opts.old_graph_hash); + if (remove_path(old_path)) + die("failed to remove path %s", old_path); + free(old_path); + + return 0; +} + static int graph_read(void) { struct object_id graph_hash; @@ -105,6 +131,8 @@ int cmd_commit_graph(int argc, const char **argv, const char *prefix) { OPTION_STRING, 'p', "pack-dir", &opts.pack_dir, N_("dir"), N_("The pack directory to store the graph") }, + OPT_BOOL('c', "clear", &opts.clear, + N_("clear graph file and graph-head")), OPT_BOOL('r', "read", &opts.read, N_("read graph file")), OPT_BOOL('w', "write", &opts.write, @@ -126,7 +154,7 @@ int cmd_commit_graph(int argc, const char **argv, const char *prefix) builtin_commit_graph_options, builtin_commit_graph_usage, 0); - if (opts.write + opts.read > 1) + if (opts.write + opts.read + opts.clear > 1) usage_with_options(builtin_commit_graph_usage, builtin_commit_graph_options); @@ -139,6 +167,8 @@ int cmd_commit_graph(int argc, const char **argv, const char *prefix) opts.has_existing = !!get_graph_head_hash(opts.pack_dir, &opts.old_graph_hash); + if (opts.clear) + return graph_clear(); if (opts.read)
Re: [PATCH v2 08/14] commit-graph: implement git-commit-graph --clear
> Teach Git to delete the current 'graph_head' file and the commit graph > it references. And will it leave other, non-important graph files behind? Looking at the code it indeed does. What is the use case for keeping the non-important graph files? > This is a good safety valve if somehow the file is > corrupted and needs to be recalculated. Since the commit graph is a > summary of contents already in the ODB, it can be regenerated. Wouldn't a simple 'git commit-graph --write --update-head' regenerate it on it's own, without cleaning first? It appears, after running a few tests, that a corrupt graph file can be recreated without cleaning, which is great. However, if graph-head is corrupt, then the command errors out with 'failed to read graph-head'. I don't understand the rationale behind this, it would be overwritten anyway, and its content is not necessary for recreating the graph. And indeed, after commenting out that get_graph_head_hash() call in cmd_commit_graph() it doesn't want to read my corrupted graph-head file, and recreates both the graph and graph-head files just fine. I think the requirement for explicitly cleaning a corrupt graph-head before re-writing it is just unnecessary complication. On second thought, what's the point of '--write' without '--update-head', when consumers (thinking 'log --topo-order...) will need the graph-head anyway? I think '--write' should create a graph-head without requiring an additional option. Hmph, another second thought: the word 'head' has a rather specific meaning in Git, although it's usually capitalized. Using this word in options and filenames may lead to confusion, especially the option '--update-head'. > Signed-off-by: Derrick Stolee > --- > Documentation/git-commit-graph.txt | 16 ++-- > builtin/commit-graph.c | 32 +++- > t/t5318-commit-graph.sh| 7 ++- > 3 files changed, 51 insertions(+), 4 deletions(-) > > diff --git a/Documentation/git-commit-graph.txt > b/Documentation/git-commit-graph.txt > index 99ced16ddc..33d6567f11 100644 > --- a/Documentation/git-commit-graph.txt > +++ b/Documentation/git-commit-graph.txt > @@ -11,6 +11,7 @@ SYNOPSIS > [verse] > 'git commit-graph' --write [--pack-dir ] > 'git commit-graph' --read [--pack-dir ] > +'git commit-graph' --clear [--pack-dir ] > > OPTIONS > --- > @@ -18,16 +19,21 @@ OPTIONS > Use given directory for the location of packfiles, graph-head, > and graph files. > > +--clear:: > + Delete the graph-head file and the graph file it references. > + (Cannot be combined with --read or --write.) > + > --read:: > Read a graph file given by the graph-head file and output basic > - details about the graph file. (Cannot be combined with --write.) > + details about the graph file. (Cannot be combined with --clear > + or --write.) > > --graph-id:: > When used with --read, consider the graph file graph-.graph. > > --write:: > Write a new graph file to the pack directory. (Cannot be combined > - with --read.) > + with --clear or --read.) All these "cannot be combined with --this and --that" remarks make subcommands more and more appealing. > > --update-head:: > When used with --write, update the graph-head file to point to > @@ -61,6 +67,12 @@ $ git commit-graph --write --update-head > $ git commit-graph --read --graph-hash= > > > +* Delete /graph-head and the file it references. > ++ > + > +$ git commit-graph --clear --pack-dir= > + > + > GIT > --- > Part of the linkgit:git[1] suite > diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c > index d73cbc907d..4970dec133 100644 > --- a/builtin/commit-graph.c > +++ b/builtin/commit-graph.c > @@ -10,6 +10,7 @@ > > static char const * const builtin_commit_graph_usage[] = { > N_("git commit-graph [--pack-dir ]"), > + N_("git commit-graph --clear [--pack-dir ]"), > N_("git commit-graph --read [--graph-hash=]"), > N_("git commit-graph --write [--pack-dir ] [--update-head]"), > NULL > @@ -17,6 +18,7 @@ static char const * const builtin_commit_graph_usage[] = { > > static struct opts_commit_graph { > const char *pack_dir; > + int clear; > int read; > const char *graph_hash; > int write; > @@ -25,6 +27,30 @@ static struct opts_commit_graph { > struct object_id old_graph_hash; > } opts; > > +static int graph_clear(void) > +{ > + struct strbuf head_path = STRBUF_INIT; > + char *old_path; > + > + if (!opts.has_existing) > + return 0; > + > + strbuf_addstr(&head_path, opts.pack_dir); > + strbuf_addstr(&head_path, "/"); > + strbuf_addstr(&head_path, "graph-head"); strbuf_addstr(&head_path, "/graph-head") Although, considering that this is the th