| author | Lars Hjemli <hjemli@gmail.com> | 2006-12-11 11:10:12 (UTC) |
|---|---|---|
| committer | Lars Hjemli <hjemli@gmail.com> | 2006-12-11 11:10:12 (UTC) |
| commit | 318d106300102c19d114a4ea89265b0a4060d9cb (patch) (side-by-side diff) | |
| tree | 3752575abec74ee0a2b544e36e3cc8f9cdfa1e66 /cgit.c | |
| parent | a581ed8d6c15b0734b082fbadf0a907c2b170423 (diff) | |
| download | cgit-318d106300102c19d114a4ea89265b0a4060d9cb.zip cgit-318d106300102c19d114a4ea89265b0a4060d9cb.tar.gz cgit-318d106300102c19d114a4ea89265b0a4060d9cb.tar.bz2 | |
Avoid infinite loops in caching layer
Add a global variable, cgit_max_lock_attemps, to avoid the possibility of
infinite loops when failing to acquire a lockfile. This could happen on
broken setups or under crazy server load.
Incidentally, this also fixes a lurking bug in cache_lock() where an
uninitialized returnvalue was used.
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
| -rw-r--r-- | cgit.c | 9 |
1 files changed, 8 insertions, 1 deletions
@@ -1,97 +1,98 @@ /* cgit.c: cgi for the git scm * * Copyright (C) 2006 Lars Hjemli * * Licensed under GNU General Public License v2 * (see COPYING for full license text) */ #include "cgit.h" const char cgit_version[] = CGIT_VERSION; const char cgit_doctype[] = "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\"\n" " \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n"; const char cgit_error[] = "<div class='error'>%s</div>"; const char cgit_lib_error[] = "<div class='error'>%s: %s</div>"; int htmlfd = 0; char *cgit_root = "/usr/src/git"; char *cgit_root_title = "Git repository browser"; char *cgit_css = "/cgit.css"; char *cgit_logo = "/git-logo.png"; char *cgit_logo_link = "http://www.kernel.org/pub/software/scm/git/docs/"; char *cgit_virtual_root = NULL; char *cgit_cache_root = "/var/cache/cgit"; +int cgit_max_lock_attempts = 5; int cgit_cache_root_ttl = 5; int cgit_cache_repo_ttl = 5; int cgit_cache_dynamic_ttl = 5; int cgit_cache_static_ttl = -1; int cgit_cache_max_create_time = 5; char *cgit_repo_name = NULL; char *cgit_repo_desc = NULL; char *cgit_repo_owner = NULL; int cgit_query_has_symref = 0; int cgit_query_has_sha1 = 0; char *cgit_querystring = NULL; char *cgit_query_repo = NULL; char *cgit_query_page = NULL; char *cgit_query_head = NULL; char *cgit_query_sha1 = NULL; struct cacheitem cacheitem; int cgit_parse_query(char *txt, configfn fn) { char *t, *value = NULL, c; if (!txt) return 0; t = txt = xstrdup(txt); while((c=*t) != '\0') { if (c=='=') { *t = '\0'; value = t+1; } else if (c=='&') { *t = '\0'; (*fn)(txt, value); txt = t+1; value = NULL; } t++; } if (t!=txt) (*fn)(txt, value); return 0; } void cgit_global_config_cb(const char *name, const char *value) { if (!strcmp(name, "root")) cgit_root = xstrdup(value); else if (!strcmp(name, "root-title")) cgit_root_title = xstrdup(value); else if (!strcmp(name, "css")) cgit_css = xstrdup(value); else if (!strcmp(name, "logo")) cgit_logo = xstrdup(value); else if (!strcmp(name, "logo-link")) cgit_logo_link = xstrdup(value); else if (!strcmp(name, "virtual-root")) cgit_virtual_root = xstrdup(value); } void cgit_repo_config_cb(const char *name, const char *value) @@ -404,105 +405,111 @@ static void cgit_print_object(char *hex) unsigned long size; if (get_sha1_hex(hex, sha1)){ htmlf(cgit_error, "Bad hex value"); return; } if (sha1_object_info(sha1, type, NULL)){ htmlf(cgit_error, "Bad object name"); return; } buf = read_sha1_file(sha1, type, &size); if (!buf) { htmlf(cgit_error, "Error reading object"); return; } buf[size] = '\0'; html("<h2>Object view</h2>"); htmlf("sha1=%s<br/>type=%s<br/>size=%i<br/>", hex, type, size); html("<pre>"); html_txt(buf); html("</pre>"); } static void cgit_print_repo_page() { if (chdir(fmt("%s/%s", cgit_root, cgit_query_repo)) || cgit_read_config("info/cgit", cgit_repo_config_cb)) { char *title = fmt("%s - %s", cgit_root_title, "Bad request"); cgit_print_docstart(title); cgit_print_pageheader(title); htmlf(cgit_lib_error, "Unable to scan repository", strerror(errno)); cgit_print_docend(); return; } setenv("GIT_DIR", fmt("%s/%s", cgit_root, cgit_query_repo), 1); char *title = fmt("%s - %s", cgit_repo_name, cgit_repo_desc); cgit_print_docstart(title); cgit_print_pageheader(title); if (!cgit_query_page) cgit_print_repo_summary(); else if (!strcmp(cgit_query_page, "log")) { cgit_print_log(cgit_query_head, 0, 100); } else if (!strcmp(cgit_query_page, "view")) { cgit_print_object(cgit_query_sha1); } cgit_print_docend(); } static void cgit_fill_cache(struct cacheitem *item) { htmlfd = item->fd; item->st.st_mtime = time(NULL); if (cgit_query_repo) cgit_print_repo_page(); else cgit_print_repolist(); } static void cgit_refresh_cache(struct cacheitem *item) { + int i = 0; + cache_prepare(item); top: + if (++i > cgit_max_lock_attempts) { + die("cgit_refresh_cache: unable to lock %s: %s", + item->name, strerror(errno)); + } if (!cache_exist(item)) { if (!cache_lock(item)) { - sched_yield(); + sleep(1); goto top; } if (!cache_exist(item)) cgit_fill_cache(item); cache_unlock(item); } else if (cache_expired(item) && cache_lock(item)) { if (cache_expired(item)) cgit_fill_cache(item); cache_unlock(item); } } static void cgit_print_cache(struct cacheitem *item) { static char buf[4096]; ssize_t i; int fd = open(item->name, O_RDONLY); if (fd<0) die("Unable to open cached file %s", item->name); while((i=read(fd, buf, sizeof(buf))) > 0) write(STDOUT_FILENO, buf, i); close(fd); } int main(int argc, const char **argv) { cgit_read_config("/etc/cgitrc", cgit_global_config_cb); cgit_querystring = xstrdup(getenv("QUERY_STRING")); cgit_parse_query(cgit_querystring, cgit_querystring_cb); cgit_refresh_cache(&cacheitem); cgit_print_cache(&cacheitem); return 0; } |