improve accuracy of function prototype in hunk headers Initial diff by Tom Jones with fixes from stsp. ok stsp@

remove gcc ternary if extension ok stsp@

collect line type metadata when generating diff Similar to line offsets, create an array of line types (i.e., hunk, context, minus, plus) for each line output in the diff. ok stsp@

sync files from got.git 58e31a80da4f4a9e10eaea148672190f35107a47 ok stsp@

avoid writing just one character at a time in diff_output_lines() With input from ori@ and millert@

fix performance issues in the search for function prototypes with + ok naddy

allow for telling the difference between empty and non-existent files Adjust labels used in diff output accordingly; non-existent files should have the label "/dev/null"

add a missing include for uint8_t and switch from <inttypes.h> to <stdint.h> ok millert stsp

allow diff API users to atomize files separately This is a breaking API change (not that we care about that at this point). This can avoid redundant work spent on atomizing a file multiple times. There are use cases where one particular file must be compared to other files over and over again, such as when blaming file history. The old API gave access to both versions of the file to the atomizer just in case a future atomizer implementation needs this. This can still be achieved by passing a second file via the atomizer's private data pointer.

C++ function prototype support based on OpenBSD's diff(1) code

search for prototypes above, not at, the first line touched by the diff chunk

add support for showing function prototypes in unidiff hunk headers

don't hex-escape non-printable ASCII in diff_output_lines(); UTF-8 must pass

atoms are stored in an array, not a list; use direct indexing instead of loop

print "\ No newline at end of file" message like UNIX diff(1) does Not adding new tests since this behaviour is covered by tests in Got.

rename diff_atom->d to diff_atom->root, because it always is The idea was that for each diff box within the files, the atoms would have a backpointer to the current layer of diff_data (indicating the current section), but it is not actually needed to update the backpointer in each atom to the current diff_data. That is why the current code always points atom->d to the root diff_data for the entire file. Clarify by proper name. Constructs like atom->d->root->foo are redundant, just use atom->root->foo.

add missing curly braces (clang reported misleading indentation)

move headers from include/diff/ to include/; makes things easier for consumers

check results of ARRAYLIST_ADD

check return value of diff_output_lines

optionally provide information about the generated diff to the API user

add APIs to write out the left and right versions of diff chunks

move some definitions from the public diff_main.h to an internal header file

convert abort() in diff_output_lines() to error return

use buffered stdio if falling back on file i/o; this is much faster