lstat_cache(): print a warning if doing ping-pong between cache types
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index 972b3daa6578776ca2f262d8e4d3290bae64e234..a5a540fd381495d2a75527b0f4fbe23ad668708f 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -12,6 +12,7 @@
 #include "run-command.h"
 #include "utf8.h"
 #include "userdiff.h"
+#include "sigchain.h"
 
 #ifdef NO_FAST_WORKING_DIRECTORY
 #define FAST_WORKING_DIRECTORY 0
@@ -170,6 +171,33 @@ static struct diff_tempfile {
        char tmp_path[PATH_MAX];
 } diff_temp[2];
 
+static struct diff_tempfile *claim_diff_tempfile(void) {
+       int i;
+       for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
+               if (!diff_temp[i].name)
+                       return diff_temp + i;
+       die("BUG: diff is failing to clean up its tempfiles");
+}
+
+static int remove_tempfile_installed;
+
+static void remove_tempfile(void)
+{
+       int i;
+       for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
+               if (diff_temp[i].name == diff_temp[i].tmp_path) {
+                       unlink(diff_temp[i].name);
+                       diff_temp[i].name = NULL;
+               }
+}
+
+static void remove_tempfile_on_signal(int signo)
+{
+       remove_tempfile();
+       sigchain_pop(signo);
+       raise(signo);
+}
+
 static int count_lines(const char *data, int size)
 {
        int count, ch, completely_empty = 1, nl_just_seen = 0;
@@ -1940,10 +1968,11 @@ static void prep_temp_blob(struct diff_tempfile *temp,
        sprintf(temp->mode, "%06o", mode);
 }
 
-static void prepare_temp_file(const char *name,
-                             struct diff_tempfile *temp,
-                             struct diff_filespec *one)
+static struct diff_tempfile *prepare_temp_file(const char *name,
+               struct diff_filespec *one)
 {
+       struct diff_tempfile *temp = claim_diff_tempfile();
+
        if (!DIFF_FILE_VALID(one)) {
        not_a_valid_file:
                /* A '-' entry produces this for file-2, and
@@ -1952,7 +1981,13 @@ static void prepare_temp_file(const char *name,
                temp->name = "/dev/null";
                strcpy(temp->hex, ".");
                strcpy(temp->mode, ".");
-               return;
+               return temp;
+       }
+
+       if (!remove_tempfile_installed) {
+               atexit(remove_tempfile);
+               sigchain_push_common(remove_tempfile_on_signal);
+               remove_tempfile_installed = 1;
        }
 
        if (!one->sha1_valid ||
@@ -1992,7 +2027,7 @@ static void prepare_temp_file(const char *name,
                         */
                        sprintf(temp->mode, "%06o", one->mode);
                }
-               return;
+               return temp;
        }
        else {
                if (diff_populate_filespec(one, 0))
@@ -2000,24 +2035,7 @@ static void prepare_temp_file(const char *name,
                prep_temp_blob(temp, one->data, one->size,
                               one->sha1, one->mode);
        }
-}
-
-static void remove_tempfile(void)
-{
-       int i;
-
-       for (i = 0; i < 2; i++)
-               if (diff_temp[i].name == diff_temp[i].tmp_path) {
-                       unlink(diff_temp[i].name);
-                       diff_temp[i].name = NULL;
-               }
-}
-
-static void remove_tempfile_on_signal(int signo)
-{
-       remove_tempfile();
-       signal(SIGINT, SIG_DFL);
-       raise(signo);
+       return temp;
 }
 
 /* An external diff command takes:
@@ -2035,34 +2053,22 @@ static void run_external_diff(const char *pgm,
                              int complete_rewrite)
 {
        const char *spawn_arg[10];
-       struct diff_tempfile *temp = diff_temp;
        int retval;
-       static int atexit_asked = 0;
-       const char *othername;
        const char **arg = &spawn_arg[0];
 
-       othername = (other? other : name);
-       if (one && two) {
-               prepare_temp_file(name, &temp[0], one);
-               prepare_temp_file(othername, &temp[1], two);
-               if (! atexit_asked &&
-                   (temp[0].name == temp[0].tmp_path ||
-                    temp[1].name == temp[1].tmp_path)) {
-                       atexit_asked = 1;
-                       atexit(remove_tempfile);
-               }
-               signal(SIGINT, remove_tempfile_on_signal);
-       }
-
        if (one && two) {
+               struct diff_tempfile *temp_one, *temp_two;
+               const char *othername = (other ? other : name);
+               temp_one = prepare_temp_file(name, one);
+               temp_two = prepare_temp_file(othername, two);
                *arg++ = pgm;
                *arg++ = name;
-               *arg++ = temp[0].name;
-               *arg++ = temp[0].hex;
-               *arg++ = temp[0].mode;
-               *arg++ = temp[1].name;
-               *arg++ = temp[1].hex;
-               *arg++ = temp[1].mode;
+               *arg++ = temp_one->name;
+               *arg++ = temp_one->hex;
+               *arg++ = temp_one->mode;
+               *arg++ = temp_two->name;
+               *arg++ = temp_two->hex;
+               *arg++ = temp_two->mode;
                if (other) {
                        *arg++ = other;
                        *arg++ = xfrm_msg;
@@ -2081,16 +2087,86 @@ static void run_external_diff(const char *pgm,
        }
 }
 
+static int similarity_index(struct diff_filepair *p)
+{
+       return p->score * 100 / MAX_SCORE;
+}
+
+static void fill_metainfo(struct strbuf *msg,
+                         const char *name,
+                         const char *other,
+                         struct diff_filespec *one,
+                         struct diff_filespec *two,
+                         struct diff_options *o,
+                         struct diff_filepair *p)
+{
+       strbuf_init(msg, PATH_MAX * 2 + 300);
+       switch (p->status) {
+       case DIFF_STATUS_COPIED:
+               strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
+               strbuf_addstr(msg, "\ncopy from ");
+               quote_c_style(name, msg, NULL, 0);
+               strbuf_addstr(msg, "\ncopy to ");
+               quote_c_style(other, msg, NULL, 0);
+               strbuf_addch(msg, '\n');
+               break;
+       case DIFF_STATUS_RENAMED:
+               strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
+               strbuf_addstr(msg, "\nrename from ");
+               quote_c_style(name, msg, NULL, 0);
+               strbuf_addstr(msg, "\nrename to ");
+               quote_c_style(other, msg, NULL, 0);
+               strbuf_addch(msg, '\n');
+               break;
+       case DIFF_STATUS_MODIFIED:
+               if (p->score) {
+                       strbuf_addf(msg, "dissimilarity index %d%%\n",
+                                   similarity_index(p));
+                       break;
+               }
+               /* fallthru */
+       default:
+               /* nothing */
+               ;
+       }
+       if (one && two && hashcmp(one->sha1, two->sha1)) {
+               int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
+
+               if (DIFF_OPT_TST(o, BINARY)) {
+                       mmfile_t mf;
+                       if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
+                           (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
+                               abbrev = 40;
+               }
+               strbuf_addf(msg, "index %.*s..%.*s",
+                           abbrev, sha1_to_hex(one->sha1),
+                           abbrev, sha1_to_hex(two->sha1));
+               if (one->mode == two->mode)
+                       strbuf_addf(msg, " %06o", one->mode);
+               strbuf_addch(msg, '\n');
+       }
+       if (msg->len)
+               strbuf_setlen(msg, msg->len - 1);
+}
+
 static void run_diff_cmd(const char *pgm,
                         const char *name,
                         const char *other,
                         const char *attr_path,
                         struct diff_filespec *one,
                         struct diff_filespec *two,
-                        const char *xfrm_msg,
+                        struct strbuf *msg,
                         struct diff_options *o,
-                        int complete_rewrite)
+                        struct diff_filepair *p)
 {
+       const char *xfrm_msg = NULL;
+       int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
+
+       if (msg) {
+               fill_metainfo(msg, name, other, one, two, o, p);
+               xfrm_msg = msg->len ? msg->buf : NULL;
+       }
+
        if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
                pgm = NULL;
        else {
@@ -2130,11 +2206,6 @@ static void diff_fill_sha1_info(struct diff_filespec *one)
                hashclr(one->sha1);
 }
 
-static int similarity_index(struct diff_filepair *p)
-{
-       return p->score * 100 / MAX_SCORE;
-}
-
 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
 {
        /* Strip the prefix but do not molest /dev/null and absolute paths */
@@ -2148,13 +2219,11 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 {
        const char *pgm = external_diff();
        struct strbuf msg;
-       char *xfrm_msg;
        struct diff_filespec *one = p->one;
        struct diff_filespec *two = p->two;
        const char *name;
        const char *other;
        const char *attr_path;
-       int complete_rewrite = 0;
 
        name  = p->one->path;
        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
@@ -2164,83 +2233,34 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 
        if (DIFF_PAIR_UNMERGED(p)) {
                run_diff_cmd(pgm, name, NULL, attr_path,
-                            NULL, NULL, NULL, o, 0);
+                            NULL, NULL, NULL, o, p);
                return;
        }
 
        diff_fill_sha1_info(one);
        diff_fill_sha1_info(two);
 
-       strbuf_init(&msg, PATH_MAX * 2 + 300);
-       switch (p->status) {
-       case DIFF_STATUS_COPIED:
-               strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
-               strbuf_addstr(&msg, "\ncopy from ");
-               quote_c_style(name, &msg, NULL, 0);
-               strbuf_addstr(&msg, "\ncopy to ");
-               quote_c_style(other, &msg, NULL, 0);
-               strbuf_addch(&msg, '\n');
-               break;
-       case DIFF_STATUS_RENAMED:
-               strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
-               strbuf_addstr(&msg, "\nrename from ");
-               quote_c_style(name, &msg, NULL, 0);
-               strbuf_addstr(&msg, "\nrename to ");
-               quote_c_style(other, &msg, NULL, 0);
-               strbuf_addch(&msg, '\n');
-               break;
-       case DIFF_STATUS_MODIFIED:
-               if (p->score) {
-                       strbuf_addf(&msg, "dissimilarity index %d%%\n",
-                                       similarity_index(p));
-                       complete_rewrite = 1;
-                       break;
-               }
-               /* fallthru */
-       default:
-               /* nothing */
-               ;
-       }
-
-       if (hashcmp(one->sha1, two->sha1)) {
-               int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
-
-               if (DIFF_OPT_TST(o, BINARY)) {
-                       mmfile_t mf;
-                       if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
-                           (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
-                               abbrev = 40;
-               }
-               strbuf_addf(&msg, "index %.*s..%.*s",
-                               abbrev, sha1_to_hex(one->sha1),
-                               abbrev, sha1_to_hex(two->sha1));
-               if (one->mode == two->mode)
-                       strbuf_addf(&msg, " %06o", one->mode);
-               strbuf_addch(&msg, '\n');
-       }
-
-       if (msg.len)
-               strbuf_setlen(&msg, msg.len - 1);
-       xfrm_msg = msg.len ? msg.buf : NULL;
-
        if (!pgm &&
            DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
            (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
-               /* a filepair that changes between file and symlink
+               /*
+                * a filepair that changes between file and symlink
                 * needs to be split into deletion and creation.
                 */
                struct diff_filespec *null = alloc_filespec(two->path);
                run_diff_cmd(NULL, name, other, attr_path,
-                            one, null, xfrm_msg, o, 0);
+                            one, null, &msg, o, p);
                free(null);
+               strbuf_release(&msg);
+
                null = alloc_filespec(one->path);
                run_diff_cmd(NULL, name, other, attr_path,
-                            null, two, xfrm_msg, o, 0);
+                            null, two, &msg, o, p);
                free(null);
        }
        else
                run_diff_cmd(pgm, name, other, attr_path,
-                            one, two, xfrm_msg, o, complete_rewrite);
+                            one, two, &msg, o, p);
 
        strbuf_release(&msg);
 }
@@ -3537,15 +3557,15 @@ void diff_unmerge(struct diff_options *options,
 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
                size_t *outsize)
 {
-       struct diff_tempfile temp;
+       struct diff_tempfile *temp;
        const char *argv[3];
        const char **arg = argv;
        struct child_process child;
        struct strbuf buf = STRBUF_INIT;
 
-       prepare_temp_file(spec->path, &temp, spec);
+       temp = prepare_temp_file(spec->path, spec);
        *arg++ = pgm;
-       *arg++ = temp.name;
+       *arg++ = temp->name;
        *arg = NULL;
 
        memset(&child, 0, sizeof(child));
@@ -3554,13 +3574,11 @@ static char *run_textconv(const char *pgm, struct diff_filespec *spec,
        if (start_command(&child) != 0 ||
            strbuf_read(&buf, child.out, 0) < 0 ||
            finish_command(&child) != 0) {
-               if (temp.name == temp.tmp_path)
-                       unlink(temp.name);
+               remove_tempfile();
                error("error running textconv command '%s'", pgm);
                return NULL;
        }
-       if (temp.name == temp.tmp_path)
-               unlink(temp.name);
+       remove_tempfile();
 
        return strbuf_detach(&buf, outsize);
 }