#include "cache.h"

#include "xdiff-interface.h"

#include "xdiff/xtypes.h"

#include "xdiff/xdiffi.h"

#include "xdiff/xemit.h"

#include "xdiff/xmacros.h"

struct xdiff_emit_state {

};

static int parse_num(char **cp_p, int *num_p)

{

char *cp = *cp_p;

int num = 0;

int read_some;

while ('0' <= *cp && *cp <= '9')

num = num * 10 + *cp++ - '0';

if (!(read_some = cp - *cp_p))

return -1;

*cp_p = cp;

*num_p = num;

return 0;

}

int parse_hunk_header(char *line, int len,

int *ob, int *on,

int *nb, int *nn)

{

char *cp;

cp = line + 4;

if (parse_num(&cp, ob)) {

bad_line:

return error("malformed diff output: %s", line);

}

if (*cp == ',') {

cp++;

if (parse_num(&cp, on))

goto bad_line;

}

else

*on = 1;

if (*cp++ != ' ' || *cp++ != '+')

goto bad_line;

if (parse_num(&cp, nb))

goto bad_line;

if (*cp == ',') {

cp++;

if (parse_num(&cp, nn))

goto bad_line;

}

else

*nn = 1;

return -!!memcmp(cp, " @@", 3);

}

static void consume_one(void *priv_, char *s, unsigned long size)

{

struct xdiff_emit_state *priv = priv_;

char *ep;

while (size) {

unsigned long this_size;

ep = memchr(s, '\n', size);

this_size = (ep == NULL) ? size : (ep - s + 1);

priv->consume(priv->consume_callback_data, s, this_size);

size -= this_size;

s += this_size;

}

}

static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)

{

struct xdiff_emit_state *priv = priv_;

int i;

for (i = 0; i < nbuf; i++) {

if (mb[i].ptr[mb[i].size-1] != '\n') {

/* Incomplete line */

strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);

continue;

}

/* we have a complete line */

if (!priv->remainder.len) {

consume_one(priv, mb[i].ptr, mb[i].size);

continue;

}

strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);

consume_one(priv, priv->remainder.buf, priv->remainder.len);

strbuf_reset(&priv->remainder);

}

if (priv->remainder.len) {

consume_one(priv, priv->remainder.buf, priv->remainder.len);

strbuf_reset(&priv->remainder);

}

return 0;

}

/*

* Trim down common substring at the end of the buffers,

* but leave at least ctx lines at the end.

*/

static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)

{

const int blk = 1024;

long trimmed = 0, recovered = 0;

char *ap = a->ptr + a->size;

char *bp = b->ptr + b->size;

long smaller = (a->size < b->size) ? a->size : b->size;

if (ctx)

return;

while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {

trimmed += blk;

ap -= blk;

bp -= blk;

}

while (recovered < trimmed)

if (ap[recovered++] == '\n')

break;

a->size -= trimmed - recovered;

b->size -= trimmed - recovered;

}

int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb)

{

mmfile_t a = *mf1;

mmfile_t b = *mf2;

trim_common_tail(&a, &b, xecfg->ctxlen);

return xdl_diff(&a, &b, xpp, xecfg, xecb);

}

int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,

xdiff_emit_consume_fn fn, void *consume_callback_data,

xpparam_t const *xpp,

xdemitconf_t const *xecfg, xdemitcb_t *xecb)

{

int ret;

struct xdiff_emit_state state;

memset(&state, 0, sizeof(state));

state.consume = fn;

state.consume_callback_data = consume_callback_data;

xecb->outf = xdiff_outf;

xecb->priv = &state;

strbuf_init(&state.remainder, 0);

ret = xdi_diff(mf1, mf2, xpp, xecfg, xecb);

strbuf_release(&state.remainder);

return ret;

}

struct xdiff_emit_hunk_state {

xdiff_emit_hunk_consume_fn consume;

void *consume_callback_data;

};

static int process_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,

xdemitconf_t const *xecfg)

{

long s1, s2, same, p_next, t_next;

xdchange_t *xch, *xche;

struct xdiff_emit_hunk_state *state = ecb->priv;

xdiff_emit_hunk_consume_fn fn = state->consume;

void *consume_callback_data = state->consume_callback_data;

for (xch = xscr; xch; xch = xche->next) {

xche = xdl_get_hunk(xch, xecfg);

s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0);

s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0);

same = s2 + XDL_MAX(xch->i1 - s1, 0);

p_next = xche->i1 + xche->chg1;

t_next = xche->i2 + xche->chg2;

fn(consume_callback_data, same, p_next, t_next);

}

return 0;

}

int xdi_diff_hunks(mmfile_t *mf1, mmfile_t *mf2,

xdiff_emit_hunk_consume_fn fn, void *consume_callback_data,

xpparam_t const *xpp, xdemitconf_t *xecfg)

{

struct xdiff_emit_hunk_state state;

xdemitcb_t ecb;

memset(&state, 0, sizeof(state));

memset(&ecb, 0, sizeof(ecb));

state.consume = fn;

state.consume_callback_data = consume_callback_data;

xecfg->emit_func = (void (*)())process_diff;

ecb.priv = &state;

return xdi_diff(mf1, mf2, xpp, xecfg, &ecb);

}

int read_mmfile(mmfile_t *ptr, const char *filename)

{

struct stat st;

FILE *f;

size_t sz;

if (stat(filename, &st))

return error("Could not stat %s", filename);

if ((f = fopen(filename, "rb")) == NULL)

return error("Could not open %s", filename);

sz = xsize_t(st.st_size);

ptr->ptr = xmalloc(sz ? sz : 1);

if (sz && fread(ptr->ptr, sz, 1, f) != 1)

return error("Could not read %s", filename);

fclose(f);

ptr->size = sz;

return 0;

}

#define FIRST_FEW_BYTES 8000

int buffer_is_binary(const char *ptr, unsigned long size)

{

if (FIRST_FEW_BYTES < size)

size = FIRST_FEW_BYTES;

return !!memchr(ptr, 0, size);

}

struct ff_regs {

};

static long ff_regexp(const char *line, long len,

char *buffer, long buffer_size, void *priv)

{

char *line_buffer;

struct ff_regs *regs = priv;

regmatch_t pmatch[2];

int i;

int result = -1;

/* Exclude terminating newline (and cr) from matching */

if (len > 0 && line[len-1] == '\n') {

if (len > 1 && line[len-2] == '\r')

len -= 2;

else

len--;

}

line_buffer = xstrndup(line, len); /* make NUL terminated */

/* Exclude terminating newline (and cr) from matching */

if (len > 0 && line[len-1] == '\n') {

if (len > 1 && line[len-2] == '\r')

len -= 2;

else

len--;

}

line_buffer = xstrndup(line, len); /* make NUL terminated */

for (i = 0; i < regs->nr; i++) {

struct ff_reg *reg = regs->array + i;

if (!regexec(&reg->re, line_buffer, 2, pmatch, 0)) {

if (reg->negate)

goto fail;

break;

}

}

if (regs->nr <= i)

goto fail;

i = pmatch[1].rm_so >= 0 ? 1 : 0;

line += pmatch[i].rm_so;

result = pmatch[i].rm_eo - pmatch[i].rm_so;

if (result > buffer_size)

result = buffer_size;

else

while (result > 0 && (isspace(line[result - 1])))

result--;

memcpy(buffer, line, result);

fail:

free(line_buffer);

return result;

}

void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value, int cflags)

{

int i;

struct ff_regs *regs;

xecfg->find_func = ff_regexp;

regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs));

for (i = 0, regs->nr = 1; value[i]; i++)

if (value[i] == '\n')

regs->nr++;

regs->array = xmalloc(regs->nr * sizeof(struct ff_reg));

for (i = 0; i < regs->nr; i++) {

struct ff_reg *reg = regs->array + i;

const char *ep = strchr(value, '\n'), *expression;

char *buffer = NULL;

reg->negate = (*value == '!');

if (reg->negate && i == regs->nr - 1)

die("Last expression must not be negated: %s", value);

if (*value == '!')

value++;

if (ep)

expression = buffer = xstrndup(value, ep - value);

else

expression = value;

if (regcomp(&reg->re, expression, cflags))

die("Invalid regexp to look for hunk header: %s", expression);

free(buffer);

value = ep + 1;

}

}

int git_xmerge_style = -1;

int git_xmerge_config(const char *var, const char *value, void *cb)

{

if (!strcasecmp(var, "merge.conflictstyle")) {

if (!value)

die("'%s' is not a boolean", var);

if (!strcmp(value, "diff3"))

git_xmerge_style = XDL_MERGE_DIFF3;

else if (!strcmp(value, "merge"))

git_xmerge_style = 0;

else

die("unknown style '%s' given for '%s'",

value, var);

return 0;

}

return git_default_config(var, value, cb);

}