diff options
Diffstat (limited to 'abspath.c')
| -rw-r--r-- | abspath.c | 186 |
1 files changed, 100 insertions, 86 deletions
@@ -15,129 +15,141 @@ int is_directory(const char *path) #define MAXDEPTH 5 /* - * Use this to get the real path, i.e. resolve links. If you want an - * absolute path but don't mind links, use absolute_path. + * Return the real path (i.e., absolute path, with symlinks resolved + * and extra slashes removed) equivalent to the specified path. (If + * you want an absolute path but don't mind links, use + * absolute_path().) The return value is a pointer to a static + * buffer. + * + * The input and all intermediate paths must be shorter than MAX_PATH. + * The directory part of path (i.e., everything up to the last + * dir_sep) must denote a valid, existing directory, but the last + * component need not exist. If die_on_error is set, then die with an + * informative error message if there is a problem. Otherwise, return + * NULL on errors (without generating any output). * * If path is our buffer, then return path, as it's already what the * user wants. */ -const char *real_path(const char *path) +static const char *real_path_internal(const char *path, int die_on_error) { - static char bufs[2][PATH_MAX + 1], *buf = bufs[0], *next_buf = bufs[1]; - char cwd[1024] = ""; - int buf_index = 1; + static struct strbuf sb = STRBUF_INIT; + char *retval = NULL; + + /* + * If we have to temporarily chdir(), store the original CWD + * here so that we can chdir() back to it at the end of the + * function: + */ + struct strbuf cwd = STRBUF_INIT; int depth = MAXDEPTH; char *last_elem = NULL; struct stat st; /* We've already done it */ - if (path == buf || path == next_buf) + if (path == sb.buf) return path; - if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX) - die ("Too long path: %.*s", 60, path); + if (!*path) { + if (die_on_error) + die("The empty string is not a valid path"); + else + goto error_out; + } + + strbuf_reset(&sb); + strbuf_addstr(&sb, path); while (depth--) { - if (!is_directory(buf)) { - char *last_slash = find_last_dir_sep(buf); + if (!is_directory(sb.buf)) { + char *last_slash = find_last_dir_sep(sb.buf); if (last_slash) { - *last_slash = '\0'; last_elem = xstrdup(last_slash + 1); + strbuf_setlen(&sb, last_slash - sb.buf + 1); } else { - last_elem = xstrdup(buf); - *buf = '\0'; + last_elem = xmemdupz(sb.buf, sb.len); + strbuf_reset(&sb); } } - if (*buf) { - if (!*cwd && !getcwd(cwd, sizeof(cwd))) - die_errno ("Could not get current working directory"); + if (sb.len) { + if (!cwd.len && strbuf_getcwd(&cwd)) { + if (die_on_error) + die_errno("Could not get current working directory"); + else + goto error_out; + } - if (chdir(buf)) - die_errno ("Could not switch to '%s'", buf); + if (chdir(sb.buf)) { + if (die_on_error) + die_errno("Could not switch to '%s'", + sb.buf); + else + goto error_out; + } + } + if (strbuf_getcwd(&sb)) { + if (die_on_error) + die_errno("Could not get current working directory"); + else + goto error_out; } - if (!getcwd(buf, PATH_MAX)) - die_errno ("Could not get current working directory"); if (last_elem) { - size_t len = strlen(buf); - if (len + strlen(last_elem) + 2 > PATH_MAX) - die ("Too long path name: '%s/%s'", - buf, last_elem); - if (len && !is_dir_sep(buf[len-1])) - buf[len++] = '/'; - strcpy(buf + len, last_elem); + if (sb.len && !is_dir_sep(sb.buf[sb.len - 1])) + strbuf_addch(&sb, '/'); + strbuf_addstr(&sb, last_elem); free(last_elem); last_elem = NULL; } - if (!lstat(buf, &st) && S_ISLNK(st.st_mode)) { - ssize_t len = readlink(buf, next_buf, PATH_MAX); - if (len < 0) - die_errno ("Invalid symlink '%s'", buf); - if (PATH_MAX <= len) - die("symbolic link too long: %s", buf); - next_buf[len] = '\0'; - buf = next_buf; - buf_index = 1 - buf_index; - next_buf = bufs[buf_index]; + if (!lstat(sb.buf, &st) && S_ISLNK(st.st_mode)) { + struct strbuf next_sb = STRBUF_INIT; + ssize_t len = strbuf_readlink(&next_sb, sb.buf, 0); + if (len < 0) { + if (die_on_error) + die_errno("Invalid symlink '%s'", + sb.buf); + else + goto error_out; + } + strbuf_swap(&sb, &next_sb); + strbuf_release(&next_sb); } else break; } - if (*cwd && chdir(cwd)) - die_errno ("Could not change back to '%s'", cwd); + retval = sb.buf; +error_out: + free(last_elem); + if (cwd.len && chdir(cwd.buf)) + die_errno("Could not change back to '%s'", cwd.buf); + strbuf_release(&cwd); - return buf; + return retval; } -static const char *get_pwd_cwd(void) +const char *real_path(const char *path) { - static char cwd[PATH_MAX + 1]; - char *pwd; - struct stat cwd_stat, pwd_stat; - if (getcwd(cwd, PATH_MAX) == NULL) - return NULL; - pwd = getenv("PWD"); - if (pwd && strcmp(pwd, cwd)) { - stat(cwd, &cwd_stat); - if ((cwd_stat.st_dev || cwd_stat.st_ino) && - !stat(pwd, &pwd_stat) && - pwd_stat.st_dev == cwd_stat.st_dev && - pwd_stat.st_ino == cwd_stat.st_ino) { - strlcpy(cwd, pwd, PATH_MAX); - } - } - return cwd; + return real_path_internal(path, 1); +} + +const char *real_path_if_valid(const char *path) +{ + return real_path_internal(path, 0); } /* * Use this to get an absolute path from a relative one. If you want * to resolve links, you should use real_path. - * - * If the path is already absolute, then return path. As the user is - * never meant to free the return value, we're safe. */ const char *absolute_path(const char *path) { - static char buf[PATH_MAX + 1]; - - if (is_absolute_path(path)) { - if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX) - die("Too long path: %.*s", 60, path); - } else { - size_t len; - const char *fmt; - const char *cwd = get_pwd_cwd(); - if (!cwd) - die_errno("Cannot determine the current working directory"); - len = strlen(cwd); - fmt = (len > 0 && is_dir_sep(cwd[len-1])) ? "%s%s" : "%s/%s"; - if (snprintf(buf, PATH_MAX, fmt, cwd, path) >= PATH_MAX) - die("Too long path: %.*s", 60, path); - } - return buf; + static struct strbuf sb = STRBUF_INIT; + strbuf_reset(&sb); + strbuf_add_absolute_path(&sb, path); + return sb.buf; } /* @@ -147,23 +159,25 @@ const char *absolute_path(const char *path) */ const char *prefix_filename(const char *pfx, int pfx_len, const char *arg) { - static char path[PATH_MAX]; -#ifndef WIN32 + static struct strbuf path = STRBUF_INIT; +#ifndef GIT_WINDOWS_NATIVE if (!pfx_len || is_absolute_path(arg)) return arg; - memcpy(path, pfx, pfx_len); - strcpy(path + pfx_len, arg); + strbuf_reset(&path); + strbuf_add(&path, pfx, pfx_len); + strbuf_addstr(&path, arg); #else char *p; /* don't add prefix to absolute paths, but still replace '\' by '/' */ + strbuf_reset(&path); if (is_absolute_path(arg)) pfx_len = 0; else if (pfx_len) - memcpy(path, pfx, pfx_len); - strcpy(path + pfx_len, arg); - for (p = path + pfx_len; *p; p++) + strbuf_add(&path, pfx, pfx_len); + strbuf_addstr(&path, arg); + for (p = path.buf + pfx_len; *p; p++) if (*p == '\\') *p = '/'; #endif - return path; + return path.buf; } |