Expand ~ and ~user in core.excludesfile, commit.template

These config variables are parsed to substitute ~ and ~user with getpw
entries.

user_path() refactored into new function expand_user_path(), to allow
dynamically allocating the return buffer.

Original patch by Karl Chen, modified by Matthieu Moy, and further
amended by Junio C Hamano.

Signed-off-by: Karl Chen <quarl@quarl.org>
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/config.txt b/Documentation/config.txt
index cd1781498eb92d7dd0d3648a8fe188fc75a6df8c..958006ca7673d0c3158fc3f8b16dcebbf11dd9eb 100644 (file)
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -380,7 +380,8 @@ Common unit suffixes of 'k', 'm', or 'g' are supported.
 core.excludesfile::
        In addition to '.gitignore' (per-directory) and
        '.git/info/exclude', git looks into this file for patterns
-       of files which are not meant to be tracked.  See
+       of files which are not meant to be tracked.  "~/" and "~user/"
+       are expanded to the specified user's home directory.  See
        linkgit:gitignore[5].
 
 core.editor::
@@ -666,6 +667,7 @@ color.ui::
 
 commit.template::
        Specify a file to use as the template for new commit messages.
+       "~/" and "~user/" are expanded to the specified user's home directory.
 
 diff.autorefreshindex::
        When using 'git-diff' to compare with work tree

diff --git a/builtin-commit.c b/builtin-commit.c
index 200ffdaad4226ae2021c86ae4b7a2f8ccefb3600..2299dc75ceebc6792fd51118aaff721cc865f844 100644 (file)
--- a/builtin-commit.c
+++ b/builtin-commit.c
@@ -954,7 +954,7 @@ static int git_commit_config(const char *k, const char *v, void *cb)
        struct wt_status *s = cb;
 
        if (!strcmp(k, "commit.template"))
-               return git_config_string(&template_file, k, v);
+               return git_config_pathname(&template_file, k, v);
 
        return git_status_config(k, v, s);
 }

diff --git a/cache.h b/cache.h
index a5eeead1e275523fbc7bc192a836193720370991..e643a9943af142e88ccf10a9777e3be3ece857dd 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -644,6 +644,7 @@ int set_shared_perm(const char *path, int mode);
 #define adjust_shared_perm(path) set_shared_perm((path), 0)
 int safe_create_leading_directories(char *path);
 int safe_create_leading_directories_const(const char *path);
+extern char *expand_user_path(const char *path);
 char *enter_repo(char *path, int strict);
 static inline int is_absolute_path(const char *path)
 {
@@ -902,6 +903,7 @@ extern unsigned long git_config_ulong(const char *, const char *);
 extern int git_config_bool_or_int(const char *, const char *, int *);
 extern int git_config_bool(const char *, const char *);
 extern int git_config_string(const char **, const char *, const char *);
+extern int git_config_pathname(const char **, const char *, const char *);
 extern int git_config_set(const char *, const char *);
 extern int git_config_set_multivar(const char *, const char *, const char *, int);
 extern int git_config_rename_section(const char *, const char *);

diff --git a/config.c b/config.c
index c64406113686e8886c0719206ce57d73fee13b29..b3d1ff4e7cc3eb6ec72aa2d5140def5de5c6966b 100644 (file)
--- a/config.c
+++ b/config.c
@@ -351,6 +351,16 @@ int git_config_string(const char **dest, const char *var, const char *value)
        return 0;
 }
 
+int git_config_pathname(const char **dest, const char *var, const char *value)
+{
+       if (!value)
+               return config_error_nonbool(var);
+       *dest = expand_user_path(value);
+       if (!*dest)
+               die("Failed to expand user dir in: '%s'", value);
+       return 0;
+}
+
 static int git_default_core_config(const char *var, const char *value)
 {
        /* This needs a better name */
@@ -474,7 +484,7 @@ static int git_default_core_config(const char *var, const char *value)
                return git_config_string(&editor_program, var, value);
 
        if (!strcmp(var, "core.excludesfile"))
-               return git_config_string(&excludes_file, var, value);
+               return git_config_pathname(&excludes_file, var, value);
 
        if (!strcmp(var, "core.whitespace")) {
                if (!value)

diff --git a/path.c b/path.c
index 047fdb0a1fe8151f5f275ca5333365df786a8abd..2470f78d3971acdf6a716e6d743e4fdaa1fc8a55 100644 (file)
--- a/path.c
+++ b/path.c
@@ -11,6 +11,7 @@
  * which is what it's designed for.
  */
 #include "cache.h"
+#include "strbuf.h"
 
 static char bad_path[] = "/bad-path/";
 
@@ -207,43 +208,44 @@ int validate_headref(const char *path)
        return -1;
 }
 
-static char *user_path(char *buf, char *path, int sz)
+static struct passwd *getpw_str(const char *username, size_t len)
 {
        struct passwd *pw;
-       char *slash;
-       int len, baselen;
+       char *username_z = xmalloc(len + 1);
+       memcpy(username_z, username, len);
+       username_z[len] = '\0';
+       pw = getpwnam(username_z);
+       free(username_z);
+       return pw;
+}
 
-       if (!path || path[0] != '~')
-               return NULL;
-       path++;
-       slash = strchr(path, '/');
-       if (path[0] == '/' || !path[0]) {
-               pw = getpwuid(getuid());
-       }
-       else {
-               if (slash) {
-                       *slash = 0;
-                       pw = getpwnam(path);
-                       *slash = '/';
-               }
-               else
-                       pw = getpwnam(path);
-       }
-       if (!pw || !pw->pw_dir || sz <= strlen(pw->pw_dir))
-               return NULL;
-       baselen = strlen(pw->pw_dir);
-       memcpy(buf, pw->pw_dir, baselen);
-       while ((1 < baselen) && (buf[baselen-1] == '/')) {
-               buf[baselen-1] = 0;
-               baselen--;
-       }
-       if (slash && slash[1]) {
-               len = strlen(slash);
-               if (sz <= baselen + len)
-                       return NULL;
-               memcpy(buf + baselen, slash, len + 1);
+/*
+ * Return a string with ~ and ~user expanded via getpw*.  If buf != NULL,
+ * then it is a newly allocated string. Returns NULL on getpw failure or
+ * if path is NULL.
+ */
+char *expand_user_path(const char *path)
+{
+       struct strbuf user_path = STRBUF_INIT;
+       const char *first_slash = strchrnul(path, '/');
+       const char *to_copy = path;
+
+       if (path == NULL)
+               goto return_null;
+       if (path[0] == '~') {
+               const char *username = path + 1;
+               size_t username_len = first_slash - username;
+               struct passwd *pw = getpw_str(username, username_len);
+               if (!pw)
+                       goto return_null;
+               strbuf_add(&user_path, pw->pw_dir, strlen(pw->pw_dir));
+               to_copy = first_slash;
        }
-       return buf;
+       strbuf_add(&user_path, to_copy, strlen(to_copy));
+       return strbuf_detach(&user_path, NULL);
+return_null:
+       strbuf_release(&user_path);
+       return NULL;
 }
 
 /*
@@ -291,8 +293,18 @@ char *enter_repo(char *path, int strict)
                if (PATH_MAX <= len)
                        return NULL;
                if (path[0] == '~') {
-                       if (!user_path(used_path, path, PATH_MAX))
+                       char *newpath = expand_user_path(path);
+                       if (!newpath || (PATH_MAX - 10 < strlen(newpath))) {
+                               free(newpath);
                                return NULL;
+                       }
+                       /*
+                        * Copy back into the static buffer. A pity
+                        * since newpath was not bounded, but other
+                        * branches of the if are limited by PATH_MAX
+                        * anyway.
+                        */
+                       strcpy(used_path, newpath); free(newpath);
                        strcpy(validated_path, path);
                        path = used_path;
                }