X-Git-Url: https://gitweb.ps.run/ps-cgit/blobdiff_plain/3eae406934b98ce78eff3a92cb410475d71095a3..e83b51b4f6bd53efea0c772e6ecdf1c5605ca611:/filter.c?ds=inline diff --git a/filter.c b/filter.c index f4ee9ac..f5a5992 100644 --- a/filter.c +++ b/filter.c @@ -12,9 +12,70 @@ #include #include #include +#include -int cgit_open_filter(struct cgit_filter *filter) +static ssize_t (*libc_write)(int fd, const void *buf, size_t count); +static ssize_t (*filter_write)(struct cgit_filter *base, const void *buf, size_t count) = NULL; +static struct cgit_filter *current_write_filter = NULL; + +static inline void reap_filter(struct cgit_filter *filter) +{ + if (filter && filter->cleanup) + filter->cleanup(filter); +} + +void cgit_cleanup_filters(void) +{ + int i; + reap_filter(ctx.cfg.about_filter); + reap_filter(ctx.cfg.commit_filter); + reap_filter(ctx.cfg.source_filter); + for (i = 0; i < cgit_repolist.count; ++i) { + reap_filter(cgit_repolist.repos[i].about_filter); + reap_filter(cgit_repolist.repos[i].commit_filter); + reap_filter(cgit_repolist.repos[i].source_filter); + } +} + +void cgit_init_filters(void) +{ + libc_write = dlsym(RTLD_NEXT, "write"); + if (!libc_write) + die("Could not locate libc's write function"); +} + +ssize_t write(int fd, const void *buf, size_t count) +{ + if (fd != STDOUT_FILENO || !filter_write) + return libc_write(fd, buf, count); + return filter_write(current_write_filter, buf, count); +} + +static inline void hook_write(struct cgit_filter *filter, ssize_t (*new_write)(struct cgit_filter *base, const void *buf, size_t count)) +{ + /* We want to avoid buggy nested patterns. */ + assert(filter_write == NULL); + assert(current_write_filter == NULL); + current_write_filter = filter; + filter_write = new_write; +} + +static inline void unhook_write() { + assert(filter_write != NULL); + assert(current_write_filter != NULL); + filter_write = NULL; + current_write_filter = NULL; +} + +static int open_exec_filter(struct cgit_filter *base, va_list ap) +{ + struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base; + int i; + + for (i = 0; i < filter->base.argument_count; i++) + filter->argv[i+1] = va_arg(ap, char *); + filter->old_stdout = chk_positive(dup(STDOUT_FILENO), "Unable to duplicate STDOUT"); chk_zero(pipe(filter->pipe_fh), "Unable to create pipe to subprocess"); @@ -33,50 +94,145 @@ int cgit_open_filter(struct cgit_filter *filter) return 0; } - -int cgit_close_filter(struct cgit_filter *filter) +static int close_exec_filter(struct cgit_filter *base) { - int exit_status; + struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base; + int i, exit_status; chk_non_negative(dup2(filter->old_stdout, STDOUT_FILENO), "Unable to restore STDOUT"); close(filter->old_stdout); if (filter->pid < 0) - return 0; + goto done; waitpid(filter->pid, &exit_status, 0); if (WIFEXITED(exit_status) && !WEXITSTATUS(exit_status)) - return 0; + goto done; die("Subprocess %s exited abnormally", filter->cmd); + +done: + for (i = 0; i < filter->base.argument_count; i++) + filter->argv[i+1] = NULL; + return 0; + } -struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype) +static void fprintf_exec_filter(struct cgit_filter *base, FILE *f, const char *prefix) +{ + struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base; + fprintf(f, "%sexec:%s\n", prefix, filter->cmd); +} + +static void cleanup_exec_filter(struct cgit_filter *base) { - struct cgit_filter *f; + struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base; + if (filter->argv) { + free(filter->argv); + filter->argv = NULL; + } + if (filter->cmd) { + free(filter->cmd); + filter->cmd = NULL; + } +} + +static struct cgit_filter *new_exec_filter(const char *cmd, int argument_count) +{ + struct cgit_exec_filter *f; int args_size = 0; - int extra_args; + + f = xmalloc(sizeof(*f)); + /* We leave argv for now and assign it below. */ + cgit_exec_filter_init(f, xstrdup(cmd), NULL); + f->base.argument_count = argument_count; + args_size = (2 + argument_count) * sizeof(char *); + f->argv = xmalloc(args_size); + memset(f->argv, 0, args_size); + f->argv[0] = f->cmd; + return &f->base; +} + +void cgit_exec_filter_init(struct cgit_exec_filter *filter, char *cmd, char **argv) +{ + memset(filter, 0, sizeof(*filter)); + filter->base.open = open_exec_filter; + filter->base.close = close_exec_filter; + filter->base.fprintf = fprintf_exec_filter; + filter->base.cleanup = cleanup_exec_filter; + filter->cmd = cmd; + filter->argv = argv; + /* The argument count for open_filter is zero by default, unless called from new_filter, above. */ + filter->base.argument_count = 0; +} + +int cgit_open_filter(struct cgit_filter *filter, ...) +{ + int result; + va_list ap; + va_start(ap, filter); + result = filter->open(filter, ap); + va_end(ap); + return result; +} + +int cgit_close_filter(struct cgit_filter *filter) +{ + return filter->close(filter); +} + +void cgit_fprintf_filter(struct cgit_filter *filter, FILE *f, const char *prefix) +{ + filter->fprintf(filter, f, prefix); +} + + + +static const struct { + const char *prefix; + struct cgit_filter *(*ctor)(const char *cmd, int argument_count); +} filter_specs[] = { + { "exec", new_exec_filter }, +}; + +struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype) +{ + char *colon; + int i; + size_t len; + int argument_count; if (!cmd || !cmd[0]) return NULL; + colon = strchr(cmd, ':'); + len = colon - cmd; + /* + * In case we're running on Windows, don't allow a single letter before + * the colon. + */ + if (len == 1) + colon = NULL; + switch (filtertype) { case SOURCE: case ABOUT: - extra_args = 1; + argument_count = 1; break; case COMMIT: default: - extra_args = 0; + argument_count = 0; break; } - - f = xmalloc(sizeof(struct cgit_filter)); - memset(f, 0, sizeof(struct cgit_filter)); - f->cmd = xstrdup(cmd); - args_size = (2 + extra_args) * sizeof(char *); - f->argv = xmalloc(args_size); - memset(f->argv, 0, args_size); - f->argv[0] = f->cmd; - return f; + /* If no prefix is given, exec filter is the default. */ + if (!colon) + return new_exec_filter(cmd, argument_count); + + for (i = 0; i < ARRAY_SIZE(filter_specs); i++) { + if (len == strlen(filter_specs[i].prefix) && + !strncmp(filter_specs[i].prefix, cmd, len)) + return filter_specs[i].ctor(colon + 1, argument_count); + } + + die("Invalid filter type: %.*s", (int) len, cmd); }