diff options
| -rw-r--r-- | include/git2/diff.h | 45 | ||||
| -rw-r--r-- | src/diff.c | 144 | ||||
| -rw-r--r-- | tests/core/structinit.c | 4 | ||||
| -rw-r--r-- | tests/diff/patchid.c | 60 | ||||
| -rw-r--r-- | tests/patch/patch_common.h | 61 |
5 files changed, 313 insertions, 1 deletions
diff --git a/include/git2/diff.h b/include/git2/diff.h index 4f0871dab..40536cb8b 100644 --- a/include/git2/diff.h +++ b/include/git2/diff.h @@ -1400,6 +1400,51 @@ GIT_EXTERN(int) git_diff_format_email_init_options( git_diff_format_email_options *opts, unsigned int version); +/** + * Patch ID options structure + * + * Initialize with `GIT_DIFF_PATCHID_OPTIONS_INIT` macro to + * correctly set the default values and version. + */ +typedef struct git_diff_patchid_options { + unsigned int version; +} git_diff_patchid_options; + +#define GIT_DIFF_PATCHID_OPTIONS_VERSION 1 +#define GIT_DIFF_PATCHID_OPTIONS_INIT { GIT_DIFF_PATCHID_OPTIONS_VERSION } + +/** + * Initialize `git_diff_patchid_options` structure. + * + * Initializes the structure with default values. Equivalent to + * creating an instance with `GIT_DIFF_PATCHID_OPTIONS_INIT`. + */ +GIT_EXTERN(int) git_diff_patchid_init_options( + git_diff_patchid_options *opts, + unsigned int version); + +/** + * Calculate the patch ID for the given patch. + * + * Calculate a stable patch ID for the given patch by summing the + * hash of the file diffs, ignoring whitespace and line numbers. + * This can be used to derive whether two diffs are the same with + * a high probability. + * + * Currently, this function only calculates stable patch IDs, as + * defined in git-patch-id(1), and should in fact generate the + * same IDs as the upstream git project does. + * + * @param out Pointer where the calculated patch ID shoul be + * stored + * @param diff The diff to calculate the ID for + * @param opts Options for how to calculate the patch ID. This is + * intended for future changes, as currently no options are + * available. + * @return 0 on success, an error code otherwise. + */ +GIT_EXTERN(int) git_diff_patchid(git_oid *out, git_diff *diff, git_diff_patchid_options *opts); + GIT_END_DECL /** @} */ diff --git a/src/diff.c b/src/diff.c index a93bd4cd0..bc4074398 100644 --- a/src/diff.c +++ b/src/diff.c @@ -19,6 +19,12 @@ #define DIFF_FLAG_SET(DIFF,FLAG,VAL) (DIFF)->opts.flags = \ (VAL) ? ((DIFF)->opts.flags | (FLAG)) : ((DIFF)->opts.flags & ~(VAL)) +struct patch_id_args { + git_hash_ctx ctx; + git_oid result; + int first_file; +}; + GIT_INLINE(const char *) diff_delta__path(const git_diff_delta *delta) { const char *str = delta->old_file.path; @@ -374,3 +380,141 @@ int git_diff_format_email_init_options( return 0; } +static int flush_hunk(git_oid *result, git_hash_ctx *ctx) +{ + git_oid hash; + unsigned short carry = 0; + int error, i; + + if ((error = git_hash_final(&hash, ctx)) < 0 || + (error = git_hash_init(ctx)) < 0) + return error; + + for (i = 0; i < GIT_OID_RAWSZ; i++) { + carry += result->id[i] + hash.id[i]; + result->id[i] = carry; + carry >>= 8; + } + + return 0; +} + +static void strip_spaces(git_buf *buf) +{ + char *src = buf->ptr, *dst = buf->ptr; + char c; + size_t len = 0; + + while ((c = *src++) != '\0') { + if (!git__isspace(c)) { + *dst++ = c; + len++; + } + } + + git_buf_truncate(buf, len); +} + +static int file_cb( + const git_diff_delta *delta, + float progress, + void *payload) +{ + struct patch_id_args *args = (struct patch_id_args *) payload; + git_buf buf = GIT_BUF_INIT; + int error; + + GIT_UNUSED(progress); + + if (!args->first_file && + (error = flush_hunk(&args->result, &args->ctx)) < 0) + goto out; + args->first_file = 0; + + if ((error = git_buf_printf(&buf, + "diff--gita/%sb/%s---a/%s+++b/%s", + delta->old_file.path, + delta->new_file.path, + delta->old_file.path, + delta->new_file.path)) < 0) + goto out; + + strip_spaces(&buf); + + if ((error = git_hash_update(&args->ctx, buf.ptr, buf.size)) < 0) + goto out; + +out: + git_buf_free(&buf); + return error; +} + +static int line_cb( + const git_diff_delta *delta, + const git_diff_hunk *hunk, + const git_diff_line *line, + void *payload) +{ + struct patch_id_args *args = (struct patch_id_args *) payload; + git_buf buf = GIT_BUF_INIT; + int error; + + GIT_UNUSED(delta); + GIT_UNUSED(hunk); + + switch (line->origin) { + case GIT_DIFF_LINE_ADDITION: + git_buf_putc(&buf, '+'); + break; + case GIT_DIFF_LINE_DELETION: + git_buf_putc(&buf, '-'); + break; + case GIT_DIFF_LINE_CONTEXT: + break; + default: + giterr_set(GITERR_PATCH, "invalid line origin for patch"); + return -1; + } + + git_buf_put(&buf, line->content, line->content_len); + strip_spaces(&buf); + + if ((error = git_hash_update(&args->ctx, buf.ptr, buf.size)) < 0) + goto out; + +out: + git_buf_free(&buf); + return error; +} + +int git_diff_patchid_init_options(git_diff_patchid_options *opts, unsigned int version) +{ + GIT_INIT_STRUCTURE_FROM_TEMPLATE( + opts, version, git_diff_patchid_options, GIT_DIFF_PATCHID_OPTIONS_INIT); + return 0; +} + +int git_diff_patchid(git_oid *out, git_diff *diff, git_diff_patchid_options *opts) +{ + struct patch_id_args args; + int error; + + GITERR_CHECK_VERSION( + opts, GIT_DIFF_PATCHID_OPTIONS_VERSION, "git_diff_patchid_options"); + + memset(&args, 0, sizeof(args)); + args.first_file = 1; + if ((error = git_hash_ctx_init(&args.ctx)) < 0) + goto out; + + if ((error = git_diff_foreach(diff, file_cb, NULL, NULL, line_cb, &args)) < 0) + goto out; + + if ((error = (flush_hunk(&args.result, &args.ctx))) < 0) + goto out; + + git_oid_cpy(out, &args.result); + +out: + return error; +} diff --git a/tests/core/structinit.c b/tests/core/structinit.c index 78503fcc6..8feba864e 100644 --- a/tests/core/structinit.c +++ b/tests/core/structinit.c @@ -176,4 +176,8 @@ void test_core_structinit__compare(void) CHECK_MACRO_FUNC_INIT_EQUAL( \ git_proxy_options, GIT_PROXY_OPTIONS_VERSION, \ GIT_PROXY_OPTIONS_INIT, git_proxy_init_options); + + CHECK_MACRO_FUNC_INIT_EQUAL( \ + git_diff_patchid_options, GIT_DIFF_PATCHID_OPTIONS_VERSION, \ + GIT_DIFF_PATCHID_OPTIONS_INIT, git_diff_patchid_init_options); } diff --git a/tests/diff/patchid.c b/tests/diff/patchid.c new file mode 100644 index 000000000..75a2aa814 --- /dev/null +++ b/tests/diff/patchid.c @@ -0,0 +1,60 @@ +#include "clar_libgit2.h" +#include "patch/patch_common.h" + +static void verify_patch_id(const char *diff_content, const char *expected_id) +{ + git_oid expected_oid, actual_oid; + git_diff *diff; + + cl_git_pass(git_oid_fromstr(&expected_oid, expected_id)); + cl_git_pass(git_diff_from_buffer(&diff, diff_content, strlen(diff_content))); + cl_git_pass(git_diff_patchid(&actual_oid, diff, NULL)); + + cl_assert_equal_oid(&expected_oid, &actual_oid); + + git_diff_free(diff); +} + +void test_diff_patchid__simple_commit(void) +{ + verify_patch_id(PATCH_SIMPLE_COMMIT, "06094b1948b878b7d9ff7560b4eae672a014b0ec"); +} + +void test_diff_patchid__filename_with_spaces(void) +{ + verify_patch_id(PATCH_APPEND_NO_NL, "f0ba05413beaef743b630e796153839462ee477a"); +} + +void test_diff_patchid__multiple_hunks(void) +{ + verify_patch_id(PATCH_MULTIPLE_HUNKS, "81e26c34643d17f521e57c483a6a637e18ba1f57"); +} + +void test_diff_patchid__multiple_files(void) +{ + verify_patch_id(PATCH_MULTIPLE_FILES, "192d1f49d23f2004517963aecd3f8a6c467f50ff"); +} + +void test_diff_patchid__same_diff_with_differing_whitespace_has_same_id(void) +{ + const char *tabs = + "diff --git a/file.txt b/file.txt\n" + "index 8fecc09..1d43a92 100644\n" + "--- a/file.txt\n" + "+++ b/file.txt\n" + "@@ -1 +1 @@\n" + "-old text\n" + "+ new text\n"; + const char *spaces = + "diff --git a/file.txt b/file.txt\n" + "index 8fecc09..1d43a92 100644\n" + "--- a/file.txt\n" + "+++ b/file.txt\n" + "@@ -1 +1 @@\n" + "-old text\n" + "+ new text\n"; + const char *id = "11efdd13c30f7a1056eac2ae2fb952da475e2c23"; + + verify_patch_id(tabs, id); + verify_patch_id(spaces, id); +} diff --git a/tests/patch/patch_common.h b/tests/patch/patch_common.h index 6ec554690..a20ebd617 100644 --- a/tests/patch/patch_common.h +++ b/tests/patch/patch_common.h @@ -253,7 +253,66 @@ "@@ -9,0 +10 @@ below it!\n" \ "+insert at end\n" -/* An insertion at the beginning and end of file (and the resultant patch) */ +#define PATCH_SIMPLE_COMMIT \ + "commit 15e119375018fba121cf58e02a9f17fe22df0df8\n" \ + "Author: Edward Thomson <ethomson@edwardthomson.com>\n" \ + "Date: Wed Jun 14 13:31:20 2017 +0200\n" \ + "\n" \ + " CHANGELOG: document git_filter_init and GIT_FILTER_INIT\n" \ + "\n" \ + "diff --git a/CHANGELOG.md b/CHANGELOG.md\n" \ + "index 1b9e0c90a..24ecba426 100644\n" \ + "--- a/CHANGELOG.md\n" \ + "+++ b/CHANGELOG.md\n" \ + "@@ -96,6 +96,9 @@ v0.26\n" \ + " * `git_transport_smart_proxy_options()' enables you to get the proxy options for\n" \ + " smart transports.\n" \ + "\n" \ + "+* The `GIT_FILTER_INIT` macro and the `git_filter_init` function are provided\n" \ + "+ to initialize a `git_filter` structure.\n" \ + "+\n" \ + " ### Breaking API changes\n" \ + "\n" \ + " * `clone_checkout_strategy` has been removed from\n" + +#define PATCH_MULTIPLE_HUNKS \ + "diff --git a/x b/x\n" \ + "index 0719398..fa0350c 100644\n" \ + "--- a/x\n" \ + "+++ b/x\n" \ + "@@ -1,5 +1,4 @@\n" \ + " 1\n" \ + "-2\n" \ + " 3\n" \ + " 4\n" \ + " 5\n" \ + "@@ -7,3 +6,4 @@\n" \ + " 7\n" \ + " 8\n" \ + " 9\n" \ + "+10\n" + +#define PATCH_MULTIPLE_FILES \ + "diff --git a/x b/x\n" \ + "index 8a1218a..7059ba5 100644\n" \ + "--- a/x\n" \ + "+++ b/x\n" \ + "@@ -1,5 +1,4 @@\n" \ + " 1\n" \ + " 2\n" \ + "-3\n" \ + " 4\n" \ + " 5\n" \ + "diff --git a/y b/y\n" \ + "index e006065..9405325 100644\n" \ + "--- a/y\n" \ + "+++ b/y\n" \ + "@@ -1,4 +1,5 @@\n" \ + " a\n" \ + " b\n" \ + "+c\n" \ + " d\n" \ + " e\n" #define FILE_PREPEND_AND_APPEND \ "first and\n" \ |