root/diff-no-index.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. read_directory_contents
  2. get_mode
  3. populate_from_stdin
  4. noindex_filespec
  5. queue_diff
  6. append_basename
  7. fixup_paths
  8. diff_no_index

/*
 * "diff --no-index" support
 * Copyright (c) 2007 by Johannes Schindelin
 * Copyright (c) 2008 by Junio C Hamano
 */

#include "cache.h"
#include "color.h"
#include "commit.h"
#include "blob.h"
#include "tag.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"
#include "log-tree.h"
#include "builtin.h"
#include "string-list.h"
#include "dir.h"

static int read_directory_contents(const char *path, struct string_list *list)
{
        DIR *dir;
        struct dirent *e;

        if (!(dir = opendir(path)))
                return error("Could not open directory %s", path);

        while ((e = readdir(dir)))
                if (!is_dot_or_dotdot(e->d_name))
                        string_list_insert(list, e->d_name);

        closedir(dir);
        return 0;
}

/*
 * This should be "(standard input)" or something, but it will
 * probably expose many more breakages in the way no-index code
 * is bolted onto the diff callchain.
 */
static const char file_from_standard_input[] = "-";

static int get_mode(const char *path, int *mode)
{
        struct stat st;

        if (!path || !strcmp(path, "/dev/null"))
                *mode = 0;
#ifdef GIT_WINDOWS_NATIVE
        else if (!strcasecmp(path, "nul"))
                *mode = 0;
#endif
        else if (path == file_from_standard_input)
                *mode = create_ce_mode(0666);
        else if (lstat(path, &st))
                return error("Could not access '%s'", path);
        else
                *mode = st.st_mode;
        return 0;
}

static int populate_from_stdin(struct diff_filespec *s)
{
        struct strbuf buf = STRBUF_INIT;
        size_t size = 0;

        if (strbuf_read(&buf, 0, 0) < 0)
                return error("error while reading from stdin %s",
                                     strerror(errno));

        s->should_munmap = 0;
        s->data = strbuf_detach(&buf, &size);
        s->size = size;
        s->should_free = 1;
        s->is_stdin = 1;
        return 0;
}

static struct diff_filespec *noindex_filespec(const char *name, int mode)
{
        struct diff_filespec *s;

        if (!name)
                name = "/dev/null";
        s = alloc_filespec(name);
        fill_filespec(s, null_sha1, 0, mode);
        if (name == file_from_standard_input)
                populate_from_stdin(s);
        return s;
}

static int queue_diff(struct diff_options *o,
                      const char *name1, const char *name2)
{
        int mode1 = 0, mode2 = 0;

        if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
                return -1;

        if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2)) {
                struct diff_filespec *d1, *d2;

                if (S_ISDIR(mode1)) {
                        /* 2 is file that is created */
                        d1 = noindex_filespec(NULL, 0);
                        d2 = noindex_filespec(name2, mode2);
                        name2 = NULL;
                        mode2 = 0;
                } else {
                        /* 1 is file that is deleted */
                        d1 = noindex_filespec(name1, mode1);
                        d2 = noindex_filespec(NULL, 0);
                        name1 = NULL;
                        mode1 = 0;
                }
                /* emit that file */
                diff_queue(&diff_queued_diff, d1, d2);

                /* and then let the entire directory be created or deleted */
        }

        if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
                struct strbuf buffer1 = STRBUF_INIT;
                struct strbuf buffer2 = STRBUF_INIT;
                struct string_list p1 = STRING_LIST_INIT_DUP;
                struct string_list p2 = STRING_LIST_INIT_DUP;
                int i1, i2, ret = 0;
                size_t len1 = 0, len2 = 0;

                if (name1 && read_directory_contents(name1, &p1))
                        return -1;
                if (name2 && read_directory_contents(name2, &p2)) {
                        string_list_clear(&p1, 0);
                        return -1;
                }

                if (name1) {
                        strbuf_addstr(&buffer1, name1);
                        if (buffer1.len && buffer1.buf[buffer1.len - 1] != '/')
                                strbuf_addch(&buffer1, '/');
                        len1 = buffer1.len;
                }

                if (name2) {
                        strbuf_addstr(&buffer2, name2);
                        if (buffer2.len && buffer2.buf[buffer2.len - 1] != '/')
                                strbuf_addch(&buffer2, '/');
                        len2 = buffer2.len;
                }

                for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
                        const char *n1, *n2;
                        int comp;

                        strbuf_setlen(&buffer1, len1);
                        strbuf_setlen(&buffer2, len2);

                        if (i1 == p1.nr)
                                comp = 1;
                        else if (i2 == p2.nr)
                                comp = -1;
                        else
                                comp = strcmp(p1.items[i1].string, p2.items[i2].string);

                        if (comp > 0)
                                n1 = NULL;
                        else {
                                strbuf_addstr(&buffer1, p1.items[i1++].string);
                                n1 = buffer1.buf;
                        }

                        if (comp < 0)
                                n2 = NULL;
                        else {
                                strbuf_addstr(&buffer2, p2.items[i2++].string);
                                n2 = buffer2.buf;
                        }

                        ret = queue_diff(o, n1, n2);
                }
                string_list_clear(&p1, 0);
                string_list_clear(&p2, 0);
                strbuf_release(&buffer1);
                strbuf_release(&buffer2);

                return ret;
        } else {
                struct diff_filespec *d1, *d2;

                if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
                        unsigned tmp;
                        const char *tmp_c;
                        tmp = mode1; mode1 = mode2; mode2 = tmp;
                        tmp_c = name1; name1 = name2; name2 = tmp_c;
                }

                d1 = noindex_filespec(name1, mode1);
                d2 = noindex_filespec(name2, mode2);
                diff_queue(&diff_queued_diff, d1, d2);
                return 0;
        }
}

/* append basename of F to D */
static void append_basename(struct strbuf *path, const char *dir, const char *file)
{
        const char *tail = strrchr(file, '/');

        strbuf_addstr(path, dir);
        while (path->len && path->buf[path->len - 1] == '/')
                path->len--;
        strbuf_addch(path, '/');
        strbuf_addstr(path, tail ? tail + 1 : file);
}

/*
 * DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
 * Note that we append the basename of F to D/, so "diff a/b/file D"
 * becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
 */
static void fixup_paths(const char **path, struct strbuf *replacement)
{
        unsigned int isdir0, isdir1;

        if (path[0] == file_from_standard_input ||
            path[1] == file_from_standard_input)
                return;
        isdir0 = is_directory(path[0]);
        isdir1 = is_directory(path[1]);
        if (isdir0 == isdir1)
                return;
        if (isdir0) {
                append_basename(replacement, path[0], path[1]);
                path[0] = replacement->buf;
        } else {
                append_basename(replacement, path[1], path[0]);
                path[1] = replacement->buf;
        }
}

void diff_no_index(struct rev_info *revs,
                   int argc, const char **argv,
                   const char *prefix)
{
        int i, prefixlen;
        const char *paths[2];
        struct strbuf replacement = STRBUF_INIT;

        diff_setup(&revs->diffopt);
        for (i = 1; i < argc - 2; ) {
                int j;
                if (!strcmp(argv[i], "--no-index"))
                        i++;
                else if (!strcmp(argv[i], "--"))
                        i++;
                else {
                        j = diff_opt_parse(&revs->diffopt, argv + i, argc - i);
                        if (j <= 0)
                                die("invalid diff option/value: %s", argv[i]);
                        i += j;
                }
        }

        prefixlen = prefix ? strlen(prefix) : 0;
        for (i = 0; i < 2; i++) {
                const char *p = argv[argc - 2 + i];
                if (!strcmp(p, "-"))
                        /*
                         * stdin should be spelled as "-"; if you have
                         * path that is "-", spell it as "./-".
                         */
                        p = file_from_standard_input;
                else if (prefixlen)
                        p = xstrdup(prefix_filename(prefix, prefixlen, p));
                paths[i] = p;
        }

        fixup_paths(paths, &replacement);

        revs->diffopt.skip_stat_unmatch = 1;
        if (!revs->diffopt.output_format)
                revs->diffopt.output_format = DIFF_FORMAT_PATCH;

        DIFF_OPT_SET(&revs->diffopt, NO_INDEX);

        revs->max_count = -2;
        diff_setup_done(&revs->diffopt);

        setup_diff_pager(&revs->diffopt);
        DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);

        if (queue_diff(&revs->diffopt, paths[0], paths[1]))
                exit(1);
        diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
        diffcore_std(&revs->diffopt);
        diff_flush(&revs->diffopt);

        strbuf_release(&replacement);

        /*
         * The return code for --no-index imitates diff(1):
         * 0 = no changes, 1 = changes, else error
         */
        exit(diff_result_code(&revs->diffopt, 0));
}

/* [<][>][^][v][top][bottom][index][help] */