/* Must be loaded before the following headers. */
#include "ldpreload.h"
+/* Disable assert()s if not compiled with --enable-debug. */
+#ifndef DEBUG
+# define NDEBUG
+#endif
+
+#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
+#include <sys/stat.h>
#include <unistd.h>
+#ifdef HAVE_ERR_H
+# include <err.h>
+#endif
#ifdef HAVE_ERROR_H
# include <error.h>
#endif
+#ifdef HAVE_STRUCT__IO_FILE__FILENO
+# include <libio.h>
+#endif
-/* Conflicting declaration in glibc. */
-#undef fwrite_unlocked
-/* These functions may be macros when compiling with hardening flags (fortify)
- * which cause build failures when used in our hook macros below. Observed
- * with Clang on Debian Wheezy. */
+/* The following functions may be macros. Undefine them or they cause build
+ * failures when used in our hook macros below. */
+
+/* In glibc, real fwrite_unlocked() is called in macro. */
+#ifdef HAVE_FWRITE_UNLOCKED
+# undef fwrite_unlocked
+#endif
+/* In Clang when compiling with hardening flags (fortify) on Debian Wheezy. */
#undef printf
#undef fprintf
+/* On FreeBSD (9.1), __swbuf() is used instead of these macros. */
+#ifdef HAVE___SWBUF
+# undef putc
+# undef putc_unlocked
+# undef putchar
+# undef putchar_unlocked
+#endif
/* Used by various functions, including debug(). */
* additional call. */
static int isatty_noinline(int fd) noinline;
static int isatty_noinline(int fd) {
+ assert(fd >= 0);
+
int saved_errno = errno;
int result = isatty(fd);
errno = saved_errno;
debug("%3d -> %3d\t\t\t[%d]\n", oldfd, newfd, getpid());
#endif
+ assert(oldfd >= 0 && newfd >= 0);
+
if (unlikely(!initialized)) {
init_from_environment();
}
debug("%3d -> .\t\t\t[%d]\n", fd, getpid());
#endif
+ assert(fd >= 0);
+
if (unlikely(!initialized)) {
init_from_environment();
}
FILE *, stream, int, flag, char const *, format, va_list, ap)
/* unlocked_stdio(3), only functions from above are hooked */
+#ifdef HAVE_FWRITE_UNLOCKED
HOOK_FILE4(size_t, fwrite_unlocked, stream,
void const *, ptr, size_t, size, size_t, nmemb, FILE *, stream)
+#endif
+#ifdef HAVE_FPUTS_UNLOCKED
HOOK_FILE2(int, fputs_unlocked, stream,
char const *, s, FILE *, stream)
+#endif
+#ifdef HAVE_FPUTC_UNLOCKED
HOOK_FILE2(int, fputc_unlocked, stream,
int, c, FILE *, stream)
+#endif
HOOK_FILE2(int, putc_unlocked, stream,
int, c, FILE *, stream)
HOOK_FILE1(int, putchar_unlocked, stdout,
int, c)
+/* glibc defines (_IO_)putc_unlocked() to a macro which either updates the
+ * output buffer or calls __overflow(). As this code is inlined we can't
+ * handle the first case, but if __overflow() is called we can color that
+ * part. As writes to stderr are never buffered, __overflow() is always called
+ * and everything works fine. This is only a problem if stdout is dupped to
+ * stderr (which shouldn't be the case too often). */
+#if defined(HAVE_STRUCT__IO_FILE__FILENO) && defined(HAVE___OVERFLOW)
+/* _IO_FILE is glibc's representation of FILE. */
+HOOK_FILE2(int, __overflow, f, _IO_FILE *, f, int, ch)
+#endif
+/* Same for FreeBSD's libc. However it's more aggressive: The inline writing
+ * and __swbuf() are also used for normal output (e.g. putc()). Writing to
+ * stderr is still fine; it always calls __swbuf() as stderr is always
+ * unbufferd. */
+#ifdef HAVE___SWBUF
+HOOK_FILE2(int, __swbuf, f, int, c, FILE *, f)
+#endif
/* perror(3) */
HOOK_VOID1(void, perror, STDERR_FILENO,
char const *, s)
-/* error(3) */
+/* err(3), non standard BSD extension */
+#ifdef HAVE_ERR_H
+HOOK_VAR_VOID2(void, err, STDERR_FILENO, verr,
+ int, eval, char const *, fmt)
+HOOK_VAR_VOID2(void, errx, STDERR_FILENO, verrx,
+ int, eval, char const *, fmt)
+HOOK_VAR_VOID1(void, warn, STDERR_FILENO, vwarn,
+ char const *, fmt)
+HOOK_VAR_VOID1(void, warnx, STDERR_FILENO, vwarnx,
+ char const *, fmt)
+HOOK_FUNC_SIMPLE3(void, verr, int, eval, const char *, fmt, va_list, args) {
+ /* Can't use verr() directly as it terminates the process which prevents
+ * the post string from being printed. */
+ vwarn(fmt, args);
+ exit(eval);
+}
+HOOK_FUNC_SIMPLE3(void, verrx, int, eval, const char *, fmt, va_list, args) {
+ /* See verr(). */
+ vwarnx(fmt, args);
+ exit(eval);
+}
+HOOK_VOID2(void, vwarn, STDERR_FILENO,
+ char const *, fmt, va_list, args)
+HOOK_VOID2(void, vwarnx, STDERR_FILENO,
+ char const *, fmt, va_list, args)
+#endif
+
+/* error(3), non-standard GNU extension */
#ifdef HAVE_ERROR_H
static void error_vararg(int status, int errnum,
char const *filename, unsigned int linenum,
/* Hook functions which duplicate file descriptors to track them. */
-static int (*real_dup)(int);
-static int (*real_dup2)(int, int);
-static int (*real_dup3)(int, int, int);
-int dup(int oldfd) {
+/* int dup(int) */
+HOOK_FUNC_DEF1(int, dup, int, oldfd) {
int newfd;
DLSYM_FUNCTION(real_dup, "dup");
return newfd;
}
-int dup2(int oldfd, int newfd) {
+/* int dup2(int, int) */
+HOOK_FUNC_DEF2(int, dup2, int, oldfd, int, newfd) {
DLSYM_FUNCTION(real_dup2, "dup2");
newfd = real_dup2(oldfd, newfd);
return newfd;
}
-int dup3(int oldfd, int newfd, int flags) {
+/* int dup3(int, int, int) */
+HOOK_FUNC_DEF3(int, dup3, int, oldfd, int, newfd, int, flags) {
DLSYM_FUNCTION(real_dup3, "dup3");
newfd = real_dup3(oldfd, newfd, flags);
return newfd;
}
-static int (*real_fcntl)(int, int, ...);
-int fcntl(int fd, int cmd, ...) {
+/* int fcntl(int, int, ...) */
+HOOK_FUNC_VAR_DEF2(int, fcntl, int, fd, int, cmd /*, ... */) {
int result;
va_list ap;
return result;
}
-static int (*real_close)(int);
-int close(int fd) {
+/* int close(int) */
+HOOK_FUNC_DEF1(int, close, int, fd) {
DLSYM_FUNCTION(real_close, "close");
- close_fd(fd);
+ if (fd >= 0) {
+ close_fd(fd);
+ }
return real_close(fd);
}
-static int (*real_fclose)(FILE *);
-int fclose(FILE *fp) {
+/* int fclose(FILE *) */
+HOOK_FUNC_DEF1(int, fclose, FILE *, fp) {
+ int fd;
+
DLSYM_FUNCTION(real_fclose, "fclose");
- close_fd(fileno(fp));
+ if (fp != NULL && (fd = fileno(fp)) >= 0) {
+ close_fd(fd);
+ }
return real_fclose(fp);
}
* ENV_NAME_FDS. It's also faster to update the environment only when
* necessary, right before the exec() to pass it to the new process. */
-static int (*real_execve)(char const *filename, char * const argv[], char * const env[]);
-int execve(char const *filename, char * const argv[], char * const env[]) {
+/* int execve(char const *, char * const [], char * const []) */
+HOOK_FUNC_DEF3(int, execve, char const *, filename, char * const *, argv, char * const *, env) {
DLSYM_FUNCTION(real_execve, "execve");
int found = 0;
/* Count arguments. */ \
size_t count = 1; /* arg */ \
va_start(ap, arg); \
- while (va_arg(ap, char const *)) { \
+ while (va_arg(ap, char *)) { \
count++; \
} \
va_end(ap); \
\
/* Copy varargs. */ \
char *args[count + 1 /* terminating NULL */]; \
- args[0] = (char *)arg; \
+ args[0] = (char *)arg; /* there's no other way around the cast */ \
\
size_t i = 1; \
va_start(ap, arg); \
int execl(char const *path, char const *arg, ...) {
EXECL_COPY_VARARGS(args);
- update_environment();
+ /* execv() updates the environment. */
return execv(path, args);
}
-
int execlp(char const *file, char const *arg, ...) {
EXECL_COPY_VARARGS(args);
- update_environment();
+ /* execvp() updates the environment. */
return execvp(file, args);
}
-
int execle(char const *path, char const *arg, ... /*, char * const envp[] */) {
+ char * const *envp;
+
EXECL_COPY_VARARGS_START(args);
/* Get envp[] located after arguments. */
- char * const *envp = va_arg(ap, char * const *);
+ envp = va_arg(ap, char * const *);
EXECL_COPY_VARARGS_END(args);
+ /* execve() updates the environment. */
return execve(path, args, envp);
}
-static int (*real_execv)(char const *path, char * const argv[]);
-int execv(char const *path, char * const argv[]) {
+/* int execv(char const *, char * const []) */
+HOOK_FUNC_DEF2(int, execv, char const *, path, char * const *, argv) {
DLSYM_FUNCTION(real_execv, "execv");
update_environment();
return real_execv(path, argv);
}
-static int (*real_execvp)(char const *path, char * const argv[]);
-int execvp(char const *file, char * const argv[]) {
+/* int execvp(char const *, char * const []) */
+HOOK_FUNC_DEF2(int, execvp, char const *, file, char * const *, argv) {
DLSYM_FUNCTION(real_execvp, "execvp");
update_environment();
/* Fake the environment so we can reuse execvp(). */
environ = (char **)envp;
+ /* execvp() updates the environment. */
return execvp(file, argv);
}
#endif
ruderich.org/simon / coloredstderr / coloredstderr.git / blobdiff