/*

* Copyright (C) 2005 Junio C Hamano

*/

#include "cache.h"

#include "quote.h"

#include "commit.h"

#include "diff.h"

#include "diffcore.h"

#include "revision.h"

#include "cache-tree.h"

#include "unpack-trees.h"

#include "refs.h"

#include "submodule.h"

#include "dir.h"

/*

* diff-files

*/

/*

* Has the work tree entity been removed?

*

* Return 1 if it was removed from the work tree, 0 if an entity to be

* compared with the cache entry ce still exists (the latter includes

* the case where a directory that is not a submodule repository

* exists for ce that is a submodule -- it is a submodule that is not

* checked out). Return negative for an error.

*/

static int check_removed(const struct cache_entry *ce, struct stat *st)

{

if (lstat(ce->name, st) < 0) {

if (errno != ENOENT && errno != ENOTDIR)

return -1;

return 1;

}

if (has_symlink_leading_path(ce->name, ce_namelen(ce)))

return 1;

if (S_ISDIR(st->st_mode)) {

unsigned char sub[20];

/*

* If ce is already a gitlink, we can have a plain

* directory (i.e. the submodule is not checked out),

* or a checked out submodule. Either case this is not

* a case where something was removed from the work tree,

* so we will return 0.

*

* Otherwise, if the directory is not a submodule

* repository, that means ce which was a blob turned into

* a directory --- the blob was removed!

*/

if (!S_ISGITLINK(ce->ce_mode) &&

resolve_gitlink_ref(ce->name, "HEAD", sub))

return 1;

}

return 0;

}

/*

* Has a file changed or has a submodule new commits or a dirty work tree?

*

* Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES

* option is set, the caller does not only want to know if a submodule is

* modified at all but wants to know all the conditions that are met (new

* commits, untracked content and/or modified content).

*/

static int match_stat_with_submodule(struct diff_options *diffopt,

const struct cache_entry *ce,

struct stat *st, unsigned ce_option,

unsigned *dirty_submodule)

{

int changed = ce_match_stat(ce, st, ce_option);

if (S_ISGITLINK(ce->ce_mode)) {

unsigned orig_flags = diffopt->flags;

if (!DIFF_OPT_TST(diffopt, OVERRIDE_SUBMODULE_CONFIG))

set_diffopt_flags_from_submodule_config(diffopt, ce->name);

if (DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES))

changed = 0;

else if (!DIFF_OPT_TST(diffopt, IGNORE_DIRTY_SUBMODULES)

&& (!changed || DIFF_OPT_TST(diffopt, DIRTY_SUBMODULES)))

*dirty_submodule = is_submodule_modified(ce->name, DIFF_OPT_TST(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES));

diffopt->flags = orig_flags;

}

return changed;

}

int run_diff_files(struct rev_info *revs, unsigned int option)

{

int entries, i;

int diff_unmerged_stage = revs->max_count;

unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)

? CE_MATCH_RACY_IS_DIRTY : 0);

diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");

if (diff_unmerged_stage < 0)

diff_unmerged_stage = 2;

entries = active_nr;

for (i = 0; i < entries; i++) {

unsigned int oldmode, newmode;

struct cache_entry *ce = active_cache[i];

int changed;

unsigned dirty_submodule = 0;

if (diff_can_quit_early(&revs->diffopt))

break;

if (!ce_path_match(ce, &revs->prune_data, NULL))

continue;

if (ce_stage(ce)) {

struct combine_diff_path *dpath;

struct diff_filepair *pair;

unsigned int wt_mode = 0;

int num_compare_stages = 0;

size_t path_len;

struct stat st;

path_len = ce_namelen(ce);

dpath = xmalloc(combine_diff_path_size(5, path_len));

dpath->path = (char *) &(dpath->parent[5]);

dpath->next = NULL;

memcpy(dpath->path, ce->name, path_len);

dpath->path[path_len] = '\0';

hashclr(dpath->sha1);

memset(&(dpath->parent[0]), 0,

sizeof(struct combine_diff_parent)*5);

changed = check_removed(ce, &st);

if (!changed)

wt_mode = ce_mode_from_stat(ce, st.st_mode);

else {

if (changed < 0) {

perror(ce->name);

continue;

}

wt_mode = 0;

}

dpath->mode = wt_mode;

while (i < entries) {

struct cache_entry *nce = active_cache[i];

int stage;

if (strcmp(ce->name, nce->name))

break;

/* Stage #2 (ours) is the first parent,

* stage #3 (theirs) is the second.

*/

stage = ce_stage(nce);

if (2 <= stage) {

int mode = nce->ce_mode;

num_compare_stages++;

hashcpy(dpath->parent[stage-2].sha1, nce->sha1);

dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);

dpath->parent[stage-2].status =

DIFF_STATUS_MODIFIED;

}

/* diff against the proper unmerged stage */

if (stage == diff_unmerged_stage)

ce = nce;

i++;

}

/*

* Compensate for loop update

*/

i--;

if (revs->combine_merges && num_compare_stages == 2) {

show_combined_diff(dpath, 2,

revs->dense_combined_merges,

revs);

free(dpath);

continue;

}

free(dpath);

dpath = NULL;

/*

* Show the diff for the 'ce' if we found the one

* from the desired stage.

*/

pair = diff_unmerge(&revs->diffopt, ce->name);

if (wt_mode)

pair->two->mode = wt_mode;

if (ce_stage(ce) != diff_unmerged_stage)

continue;

}

if (ce_uptodate(ce) || ce_skip_worktree(ce))

continue;

/* If CE_VALID is set, don't look at workdir for file removal */

if (ce->ce_flags & CE_VALID) {

changed = 0;

newmode = ce->ce_mode;

} else {

struct stat st;

changed = check_removed(ce, &st);

if (changed) {

if (changed < 0) {

perror(ce->name);

continue;

}

diff_addremove(&revs->diffopt, '-', ce->ce_mode,

ce->sha1, !is_null_sha1(ce->sha1),

ce->name, 0);

continue;

}

changed = match_stat_with_submodule(&revs->diffopt, ce, &st,

ce_option, &dirty_submodule);

newmode = ce_mode_from_stat(ce, st.st_mode);

}

if (!changed && !dirty_submodule) {

ce_mark_uptodate(ce);

if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))

continue;

}

oldmode = ce->ce_mode;

diff_change(&revs->diffopt, oldmode, newmode,

ce->sha1, (changed ? null_sha1 : ce->sha1),

!is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),

ce->name, 0, dirty_submodule);

}

diffcore_std(&revs->diffopt);

diff_flush(&revs->diffopt);

return 0;

}

/*

* diff-index

*/

/* A file entry went away or appeared */

static void diff_index_show_file(struct rev_info *revs,

unsigned dirty_submodule)

{

diff_addremove(&revs->diffopt, prefix[0], mode,

sha1, sha1_valid, ce->name, dirty_submodule);

}

static int get_stat_data(const struct cache_entry *ce,

unsigned *dirty_submodule, struct diff_options *diffopt)

{

const unsigned char *sha1 = ce->sha1;

unsigned int mode = ce->ce_mode;

if (!cached && !ce_uptodate(ce)) {

int changed;

struct stat st;

changed = check_removed(ce, &st);

if (changed < 0)

return -1;

else if (changed) {

if (match_missing) {

*sha1p = sha1;

*modep = mode;

return 0;

}

return -1;

}

changed = match_stat_with_submodule(diffopt, ce, &st,

0, dirty_submodule);

if (changed) {

mode = ce_mode_from_stat(ce, st.st_mode);

sha1 = null_sha1;

}

}

*sha1p = sha1;

*modep = mode;

return 0;

}

static void show_new_file(struct rev_info *revs,

const struct cache_entry *new,

int cached, int match_missing)

{

const unsigned char *sha1;

unsigned int mode;

unsigned dirty_submodule = 0;

/*

* New file in the index: it might actually be different in

* the working tree.

*/

if (get_stat_data(new, &sha1, &mode, cached, match_missing,

&dirty_submodule, &revs->diffopt) < 0)

return;

diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);

}

static int show_modified(struct rev_info *revs,

int cached, int match_missing)

{

unsigned int mode, oldmode;

const unsigned char *sha1;

unsigned dirty_submodule = 0;

if (get_stat_data(new, &sha1, &mode, cached, match_missing,

&dirty_submodule, &revs->diffopt) < 0) {

if (report_missing)

diff_index_show_file(revs, "-", old,

old->sha1, 1, old->ce_mode, 0);

return -1;

}

if (revs->combine_merges && !cached &&

(hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {

struct combine_diff_path *p;

int pathlen = ce_namelen(new);

p = xmalloc(combine_diff_path_size(2, pathlen));

p->path = (char *) &p->parent[2];

p->next = NULL;

memcpy(p->path, new->name, pathlen);

p->path[pathlen] = 0;

p->mode = mode;

hashclr(p->sha1);

memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));

p->parent[0].status = DIFF_STATUS_MODIFIED;

p->parent[0].mode = new->ce_mode;

hashcpy(p->parent[0].sha1, new->sha1);

p->parent[1].status = DIFF_STATUS_MODIFIED;

p->parent[1].mode = old->ce_mode;

hashcpy(p->parent[1].sha1, old->sha1);

show_combined_diff(p, 2, revs->dense_combined_merges, revs);

free(p);

return 0;

}

oldmode = old->ce_mode;

if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&

!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))

return 0;

diff_change(&revs->diffopt, oldmode, mode,

old->sha1, sha1, 1, !is_null_sha1(sha1),

old->name, 0, dirty_submodule);

return 0;

}

/*

* This gets a mix of an existing index and a tree, one pathname entry

* at a time. The index entry may be a single stage-0 one, but it could

* also be multiple unmerged entries (in which case idx_pos/idx_nr will

* give you the position and number of entries in the index).

*/

static void do_oneway_diff(struct unpack_trees_options *o,

const struct cache_entry *idx,

const struct cache_entry *tree)

{

struct rev_info *revs = o->unpack_data;

int match_missing, cached;

/* if the entry is not checked out, don't examine work tree */

cached = o->index_only ||

(idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));

/*

* Backward compatibility wart - "diff-index -m" does

* not mean "do not ignore merges", but "match_missing".

*

* But with the revision flag parsing, that's found in

* "!revs->ignore_merges".

*/

match_missing = !revs->ignore_merges;

if (cached && idx && ce_stage(idx)) {

struct diff_filepair *pair;

pair = diff_unmerge(&revs->diffopt, idx->name);

if (tree)

fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);

return;

}

/*

* Something added to the tree?

*/

if (!tree) {

show_new_file(revs, idx, cached, match_missing);

return;

}

/*

* Something removed from the tree?

*/

if (!idx) {

diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);

return;

}

/* Show difference between old and new */

show_modified(revs, tree, idx, 1, cached, match_missing);

}

/*

* The unpack_trees() interface is designed for merging, so

* the different source entries are designed primarily for

* the source trees, with the old index being really mainly

* used for being replaced by the result.

*

* For diffing, the index is more important, and we only have a

* single tree.

*

* We're supposed to advance o->pos to skip what we have already processed.

*

* This wrapper makes it all more readable, and takes care of all

* the fairly complex unpack_trees() semantic requirements, including

* the skipping, the path matching, the type conflict cases etc.

*/

static int oneway_diff(const struct cache_entry * const *src,

struct unpack_trees_options *o)

{

const struct cache_entry *idx = src[0];

const struct cache_entry *tree = src[1];

struct rev_info *revs = o->unpack_data;

/*

* Unpack-trees generates a DF/conflict entry if

* there was a directory in the index and a tree

* in the tree. From a diff standpoint, that's a

* delete of the tree and a create of the file.

*/

if (tree == o->df_conflict_entry)

tree = NULL;

if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {

do_oneway_diff(o, idx, tree);

if (diff_can_quit_early(&revs->diffopt)) {

o->exiting_early = 1;

return -1;

}

}

return 0;

}

static int diff_cache(struct rev_info *revs,

const unsigned char *tree_sha1,

const char *tree_name,

int cached)

{

struct tree *tree;

struct tree_desc t;

struct unpack_trees_options opts;

tree = parse_tree_indirect(tree_sha1);

if (!tree)

return error("bad tree object %s",

tree_name ? tree_name : sha1_to_hex(tree_sha1));

memset(&opts, 0, sizeof(opts));

opts.head_idx = 1;

opts.index_only = cached;

opts.diff_index_cached = (cached &&

!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));

opts.merge = 1;

opts.fn = oneway_diff;

opts.unpack_data = revs;

opts.src_index = &the_index;

opts.dst_index = NULL;

opts.pathspec = &revs->diffopt.pathspec;

opts.pathspec->recursive = 1;

init_tree_desc(&t, tree->buffer, tree->size);

return unpack_trees(1, &t, &opts);

}

int run_diff_index(struct rev_info *revs, int cached)

{

struct object_array_entry *ent;

ent = revs->pending.objects;

if (diff_cache(revs, ent->item->sha1, ent->name, cached))

exit(128);

diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");

diffcore_fix_diff_index(&revs->diffopt);

diffcore_std(&revs->diffopt);

diff_flush(&revs->diffopt);

return 0;

}

int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)

{

struct rev_info revs;

init_revisions(&revs, NULL);

copy_pathspec(&revs.prune_data, &opt->pathspec);

revs.diffopt = *opt;

if (diff_cache(&revs, tree_sha1, NULL, 1))

exit(128);

return 0;

}

int index_differs_from(const char *def, int diff_flags)

{

struct rev_info rev;

struct setup_revision_opt opt;

init_revisions(&rev, NULL);

memset(&opt, 0, sizeof(opt));

opt.def = def;

setup_revisions(0, NULL, &rev, &opt);

DIFF_OPT_SET(&rev.diffopt, QUICK);

DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);

rev.diffopt.flags |= diff_flags;

run_diff_index(&rev, 1);

if (rev.pending.alloc)

free(rev.pending.objects);

return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);

}