From 530e741c726a612d78de21957d531dd2215483b4 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Sat, 24 Nov 2007 23:48:04 -0800 Subject: Start preparing the API documents. Most of them are still stubs, but the procedure to build the HTML documentation, maintaining the index and installing the end product are there. I placed names of people who are likely to know the most about the topic in the stub files, so that volunteers will know whom to ask questions as needed. Signed-off-by: Junio C Hamano --- Documentation/technical/api-allocation-growing.txt | 34 ++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 Documentation/technical/api-allocation-growing.txt (limited to 'Documentation/technical/api-allocation-growing.txt') diff --git a/Documentation/technical/api-allocation-growing.txt b/Documentation/technical/api-allocation-growing.txt new file mode 100644 index 0000000000..43dbe09f73 --- /dev/null +++ b/Documentation/technical/api-allocation-growing.txt @@ -0,0 +1,34 @@ +allocation growing API +====================== + +Dynamically growing an array using realloc() is error prone and boring. + +Define your array with: + +* a pointer (`ary`) that points at the array, initialized to `NULL`; + +* an integer variable (`alloc`) that keeps track of how big the current + allocation is, initialized to `0`; + +* another integer variable (`nr`) to keep track of how many elements the + array currently has, initialized to `0`. + +Then before adding `n`th element to the array, call `ALLOC_GROW(ary, n, +alloc)`. This ensures that the array can hold at least `n` elements by +calling `realloc(3)` and adjusting `alloc` variable. + +------------ +sometype *ary; +size_t nr; +size_t alloc + +for (i = 0; i < nr; i++) + if (we like ary[i] already) + return; + +/* we did not like any existing one, so add one */ +ALLOC_GROW(ary, nr + 1, alloc); +ary[nr++] = value you like; +------------ + +You are responsible for updating the `nr` variable. -- cgit v1.2.3