summaryrefslogtreecommitdiff
path: root/Documentation/technical
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/technical')
-rw-r--r--Documentation/technical/api-builtin.txt2
-rw-r--r--Documentation/technical/api-gitattributes.txt61
-rw-r--r--Documentation/technical/api-ref-iteration.txt81
-rw-r--r--Documentation/technical/api-string-list.txt10
-rw-r--r--Documentation/technical/index-format.txt5
-rw-r--r--Documentation/technical/pack-protocol.txt103
6 files changed, 209 insertions, 53 deletions
diff --git a/Documentation/technical/api-builtin.txt b/Documentation/technical/api-builtin.txt
index 5cb2b0590a..b0cafe87be 100644
--- a/Documentation/technical/api-builtin.txt
+++ b/Documentation/technical/api-builtin.txt
@@ -49,6 +49,8 @@ Additionally, if `foo` is a new command, there are 3 more things to do:
. Add an entry for `git-foo` to `command-list.txt`.
+. Add an entry for `/git-foo` to `.gitignore`.
+
How a built-in is called
------------------------
diff --git a/Documentation/technical/api-gitattributes.txt b/Documentation/technical/api-gitattributes.txt
index 9d97eaa9de..ce363b6305 100644
--- a/Documentation/technical/api-gitattributes.txt
+++ b/Documentation/technical/api-gitattributes.txt
@@ -11,27 +11,15 @@ Data Structure
`struct git_attr`::
An attribute is an opaque object that is identified by its name.
- Pass the name and its length to `git_attr()` function to obtain
- the object of this type. The internal representation of this
- structure is of no interest to the calling programs.
+ Pass the name to `git_attr()` function to obtain the object of
+ this type. The internal representation of this structure is
+ of no interest to the calling programs. The name of the
+ attribute can be retrieved by calling `git_attr_name()`.
`struct git_attr_check`::
This structure represents a set of attributes to check in a call
- to `git_checkattr()` function, and receives the results.
-
-
-Calling Sequence
-----------------
-
-* Prepare an array of `struct git_attr_check` to define the list of
- attributes you would want to check. To populate this array, you would
- need to define necessary attributes by calling `git_attr()` function.
-
-* Call git_checkattr() to check the attributes for the path.
-
-* Inspect `git_attr_check` structure to see how each of the attribute in
- the array is defined for the path.
+ to `git_check_attr()` function, and receives the results.
Attribute Values
@@ -57,6 +45,19 @@ If none of the above returns true, `.value` member points at a string
value of the attribute for the path.
+Querying Specific Attributes
+----------------------------
+
+* Prepare an array of `struct git_attr_check` to define the list of
+ attributes you would want to check. To populate this array, you would
+ need to define necessary attributes by calling `git_attr()` function.
+
+* Call `git_check_attr()` to check the attributes for the path.
+
+* Inspect `git_attr_check` structure to see how each of the attribute in
+ the array is defined for the path.
+
+
Example
-------
@@ -72,18 +73,18 @@ static void setup_check(void)
{
if (check[0].attr)
return; /* already done */
- check[0].attr = git_attr("crlf", 4);
- check[1].attr = git_attr("ident", 5);
+ check[0].attr = git_attr("crlf");
+ check[1].attr = git_attr("ident");
}
------------
-. Call `git_checkattr()` with the prepared array of `struct git_attr_check`:
+. Call `git_check_attr()` with the prepared array of `struct git_attr_check`:
------------
const char *path;
setup_check();
- git_checkattr(path, ARRAY_SIZE(check), check);
+ git_check_attr(path, ARRAY_SIZE(check), check);
------------
. Act on `.value` member of the result, left in `check[]`:
@@ -108,4 +109,20 @@ static void setup_check(void)
}
------------
-(JC)
+
+Querying All Attributes
+-----------------------
+
+To get the values of all attributes associated with a file:
+
+* Call `git_all_attrs()`, which returns an array of `git_attr_check`
+ structures.
+
+* Iterate over the `git_attr_check` array to examine the attribute
+ names and values. The name of the attribute described by a
+ `git_attr_check` object can be retrieved via
+ `git_attr_name(check[i].attr)`. (Please note that no items will be
+ returned for unset attributes, so `ATTR_UNSET()` will return false
+ for all returned `git_array_check` objects.)
+
+* Free the `git_array_check` array.
diff --git a/Documentation/technical/api-ref-iteration.txt b/Documentation/technical/api-ref-iteration.txt
new file mode 100644
index 0000000000..dbbea95db7
--- /dev/null
+++ b/Documentation/technical/api-ref-iteration.txt
@@ -0,0 +1,81 @@
+ref iteration API
+=================
+
+
+Iteration of refs is done by using an iterate function which will call a
+callback function for every ref. The callback function has this
+signature:
+
+ int handle_one_ref(const char *refname, const unsigned char *sha1,
+ int flags, void *cb_data);
+
+There are different kinds of iterate functions which all take a
+callback of this type. The callback is then called for each found ref
+until the callback returns nonzero. The returned value is then also
+returned by the iterate function.
+
+Iteration functions
+-------------------
+
+* `head_ref()` just iterates the head ref.
+
+* `for_each_ref()` iterates all refs.
+
+* `for_each_ref_in()` iterates all refs which have a defined prefix and
+ strips that prefix from the passed variable refname.
+
+* `for_each_tag_ref()`, `for_each_branch_ref()`, `for_each_remote_ref()`,
+ `for_each_replace_ref()` iterate refs from the respective area.
+
+* `for_each_glob_ref()` iterates all refs that match the specified glob
+ pattern.
+
+* `for_each_glob_ref_in()` the previous and `for_each_ref_in()` combined.
+
+* `head_ref_submodule()`, `for_each_ref_submodule()`,
+ `for_each_ref_in_submodule()`, `for_each_tag_ref_submodule()`,
+ `for_each_branch_ref_submodule()`, `for_each_remote_ref_submodule()`
+ do the same as the functions descibed above but for a specified
+ submodule.
+
+* `for_each_rawref()` can be used to learn about broken ref and symref.
+
+* `for_each_reflog()` iterates each reflog file.
+
+Submodules
+----------
+
+If you want to iterate the refs of a submodule you first need to add the
+submodules object database. You can do this by a code-snippet like
+this:
+
+ const char *path = "path/to/submodule"
+ if (!add_submodule_odb(path))
+ die("Error submodule '%s' not populated.", path);
+
+`add_submodule_odb()` will return an non-zero value on success. If you
+do not do this you will get an error for each ref that it does not point
+to a valid object.
+
+Note: As a side-effect of this you can not safely assume that all
+objects you lookup are available in superproject. All submodule objects
+will be available the same way as the superprojects objects.
+
+Example:
+--------
+
+----
+static int handle_remote_ref(const char *refname,
+ const unsigned char *sha1, int flags, void *cb_data)
+{
+ struct strbuf *output = cb_data;
+ strbuf_addf(output, "%s\n", refname);
+ return 0;
+}
+
+...
+
+ struct strbuf output = STRBUF_INIT;
+ for_each_remote_ref(handle_remote_ref, &output);
+ printf("%s", output.buf);
+----
diff --git a/Documentation/technical/api-string-list.txt b/Documentation/technical/api-string-list.txt
index 3f575bdcff..ce24eb96f5 100644
--- a/Documentation/technical/api-string-list.txt
+++ b/Documentation/technical/api-string-list.txt
@@ -29,6 +29,9 @@ member (you need this if you add things later) and you should set the
. Can sort an unsorted list using `sort_string_list`.
+. Can remove individual items of an unsorted list using
+ `unsorted_string_list_delete_item`.
+
. Finally it should free the list using `string_list_clear`.
Example:
@@ -112,6 +115,13 @@ write `string_list_insert(...)->util = ...;`.
The above two functions need to look through all items, as opposed to their
counterpart for sorted lists, which performs a binary search.
+`unsorted_string_list_delete_item`::
+
+ Remove an item from a string_list. The `string` pointer of the items
+ will be freed in case the `strdup_strings` member of the string_list
+ is set. The third parameter controls if the `util` pointer of the
+ items should be freed or not.
+
Data structures
---------------
diff --git a/Documentation/technical/index-format.txt b/Documentation/technical/index-format.txt
index 7b233ca196..8930b3fabc 100644
--- a/Documentation/technical/index-format.txt
+++ b/Documentation/technical/index-format.txt
@@ -147,8 +147,9 @@ GIT index format
- 160-bit object name for the object that would result from writing
this span of index as a tree.
- An entry can be in an invalidated state and is represented by having -1
- in the entry_count field.
+ An entry can be in an invalidated state and is represented by having
+ -1 in the entry_count field. In this case, there is no object name
+ and the next entry starts immediately after the newline.
The entries are written out in the top-down, depth-first order. The
first entry represents the root level of the repository, followed by the
diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index 369f91d3b9..a7004c63e7 100644
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -179,34 +179,36 @@ and descriptions.
Packfile Negotiation
--------------------
-After reference and capabilities discovery, the client can decide
-to terminate the connection by sending a flush-pkt, telling the
-server it can now gracefully terminate (as happens with the ls-remote
-command) or it can enter the negotiation phase, where the client and
-server determine what the minimal packfile necessary for transport is.
-
-Once the client has the initial list of references that the server
-has, as well as the list of capabilities, it will begin telling the
-server what objects it wants and what objects it has, so the server
-can make a packfile that only contains the objects that the client needs.
-The client will also send a list of the capabilities it wants to be in
-effect, out of what the server said it could do with the first 'want' line.
+After reference and capabilities discovery, the client can decide to
+terminate the connection by sending a flush-pkt, telling the server it can
+now gracefully terminate, and disconnect, when it does not need any pack
+data. This can happen with the ls-remote command, and also can happen when
+the client already is up-to-date.
+
+Otherwise, it enters the negotiation phase, where the client and
+server determine what the minimal packfile necessary for transport is,
+by telling the server what objects it wants, its shallow objects
+(if any), and the maximum commit depth it wants (if any). The client
+will also send a list of the capabilities it wants to be in effect,
+out of what the server said it could do with the first 'want' line.
----
upload-request = want-list
- have-list
- compute-end
+ *shallow-line
+ *1depth-request
+ flush-pkt
want-list = first-want
*additional-want
- flush-pkt
+
+ shallow-line = PKT_LINE("shallow" SP obj-id)
+
+ depth-request = PKT_LINE("deepen" SP depth)
first-want = PKT-LINE("want" SP obj-id SP capability-list LF)
additional-want = PKT-LINE("want" SP obj-id LF)
- have-list = *have-line
- have-line = PKT-LINE("have" SP obj-id LF)
- compute-end = flush-pkt / PKT-LINE("done")
+ depth = 1*DIGIT
----
Clients MUST send all the obj-ids it wants from the reference
@@ -215,21 +217,64 @@ discovery phase as 'want' lines. Clients MUST send at least one
obj-id in a 'want' command which did not appear in the response
obtained through ref discovery.
-If client is requesting a shallow clone, it will now send a 'deepen'
-line with the depth it is requesting.
+The client MUST write all obj-ids which it only has shallow copies
+of (meaning that it does not have the parents of a commit) as
+'shallow' lines so that the server is aware of the limitations of
+the client's history. Clients MUST NOT mention an obj-id which
+it does not know exists on the server.
+
+The client now sends the maximum commit history depth it wants for
+this transaction, which is the number of commits it wants from the
+tip of the history, if any, as a 'deepen' line. A depth of 0 is the
+same as not making a depth request. The client does not want to receive
+any commits beyond this depth, nor objects needed only to complete
+those commits. Commits whose parents are not received as a result are
+defined as shallow and marked as such in the server. This information
+is sent back to the client in the next step.
+
+Once all the 'want's and 'shallow's (and optional 'deepen') are
+transferred, clients MUST send a flush-pkt, to tell the server side
+that it is done sending the list.
+
+Otherwise, if the client sent a positive depth request, the server
+will determine which commits will and will not be shallow and
+send this information to the client. If the client did not request
+a positive depth, this step is skipped.
-Once all the "want"s (and optional 'deepen') are transferred,
-clients MUST send a flush-pkt. If the client has all the references
-on the server, client flushes and disconnects.
+----
+ shallow-update = *shallow-line
+ *unshallow-line
+ flush-pkt
-TODO: shallow/unshallow response and document the deepen command in the ABNF.
+ shallow-line = PKT-LINE("shallow" SP obj-id)
+
+ unshallow-line = PKT-LINE("unshallow" SP obj-id)
+----
+
+If the client has requested a positive depth, the server will compute
+the set of commits which are no deeper than the desired depth, starting
+at the client's wants. The server writes 'shallow' lines for each
+commit whose parents will not be sent as a result. The server writes
+an 'unshallow' line for each commit which the client has indicated is
+shallow, but is no longer shallow at the currently requested depth
+(that is, its parents will now be sent). The server MUST NOT mark
+as unshallow anything which the client has not indicated was shallow.
Now the client will send a list of the obj-ids it has using 'have'
-lines. In multi_ack mode, the canonical implementation will send up
-to 32 of these at a time, then will send a flush-pkt. The canonical
-implementation will skip ahead and send the next 32 immediately,
-so that there is always a block of 32 "in-flight on the wire" at a
-time.
+lines, so the server can make a packfile that only contains the objects
+that the client needs. In multi_ack mode, the canonical implementation
+will send up to 32 of these at a time, then will send a flush-pkt. The
+canonical implementation will skip ahead and send the next 32 immediately,
+so that there is always a block of 32 "in-flight on the wire" at a time.
+
+----
+ upload-haves = have-list
+ compute-end
+
+ have-list = *have-line
+ have-line = PKT-LINE("have" SP obj-id LF)
+ compute-end = flush-pkt / PKT-LINE("done")
+----
If the server reads 'have' lines, it then will respond by ACKing any
of the obj-ids the client said it had that the server also has. The