mirror of
https://github.com/git/git.git
synced 2024-11-17 06:25:13 +01:00
c1189caeaf
The submodule code recently grew generic code to build a
dynamic argv array. Many other parts of the code can reuse
this, too, so let's make it generically available.
There are two enhancements not found in the original code:
1. We now handle the NULL-termination invariant properly,
even when no strings have been pushed (before, you
could have an empty, NULL argv). This was not a problem
for the submodule code, which always pushed at least
one argument, but was not sufficiently safe for
generic code.
2. There is a formatted variant of the "push" function.
This is a convenience function which was not needed by
the submodule code, but will make it easier to port
other users to the new code.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
46 lines
1.6 KiB
Text
46 lines
1.6 KiB
Text
argv-array API
|
|
==============
|
|
|
|
The argv-array API allows one to dynamically build and store
|
|
NULL-terminated lists. An argv-array maintains the invariant that the
|
|
`argv` member always points to a non-NULL array, and that the array is
|
|
always NULL-terminated at the element pointed to by `argv[argc]`. This
|
|
makes the result suitable for passing to functions expecting to receive
|
|
argv from main(), or the link:api-run-command.html[run-command API].
|
|
|
|
The link:api-string-list.html[string-list API] is similar, but cannot be
|
|
used for these purposes; instead of storing a straight string pointer,
|
|
it contains an item structure with a `util` field that is not compatible
|
|
with the traditional argv interface.
|
|
|
|
Each `argv_array` manages its own memory. Any strings pushed into the
|
|
array are duplicated, and all memory is freed by argv_array_clear().
|
|
|
|
Data Structures
|
|
---------------
|
|
|
|
`struct argv_array`::
|
|
|
|
A single array. This should be initialized by assignment from
|
|
`ARGV_ARRAY_INIT`, or by calling `argv_array_init`. The `argv`
|
|
member contains the actual array; the `argc` member contains the
|
|
number of elements in the array, not including the terminating
|
|
NULL.
|
|
|
|
Functions
|
|
---------
|
|
|
|
`argv_array_init`::
|
|
Initialize an array. This is no different than assigning from
|
|
`ARGV_ARRAY_INIT`.
|
|
|
|
`argv_array_push`::
|
|
Push a copy of a string onto the end of the array.
|
|
|
|
`argv_array_pushf`::
|
|
Format a string and push it onto the end of the array. This is a
|
|
convenience wrapper combining `strbuf_addf` and `argv_array_push`.
|
|
|
|
`argv_array_clear`::
|
|
Free all memory associated with the array and return it to the
|
|
initial, empty state.
|