significantly overhaul output helpers

There are a few major points we want to hit here:
 - have all output from libsandbox go through portage helpers when we are
   in the portage environment so that output is properly logged
 - convert SB_E{info,warn,error} to sb_e{info,warn,error} to match style
   of other functions and cut down on confusion
 - move all abort/output helpers to libsbutil so it can be used in all
   source trees and not just by libsandbox
 - migrate all abort points to the centralized sb_ebort helper

Unfortunately, it's not terribly easy to untangle these into separate
patches, but hopefully this shouldn't be too messy as much of it is
mechanical: move funcs between files, and change the name of funcs
that get called.

URL: http://bugs.gentoo.org/278761
Reported-by: Mounir Lamouri <volkmar@gentoo.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

8 files changed, 321 insertions, 62 deletions

diff --git a/libsbutil/Makefile.am b/libsbutil/Makefile.am
index f1feca3..49a7d3b 100644
--- a/libsbutil/Makefile.am
+++ b/libsbutil/Makefile.am
@@ -20,11 +20,15 @@ libsbutil_la_SOURCES =                        \
 	get_tmp_dir.c                         \
 	is_env_on.c                           \
 	is_env_off.c                          \
+	sb_backtrace.c                        \
+	sb_efuncs.c                           \
 	sb_open.c                             \
 	sb_read.c                             \
 	sb_write.c                            \
+	sb_write_fd.c                         \
 	sb_close.c                            \
 	sb_printf.c                           \
+	sb_proc.c                             \
 	sb_memory.c                           \
 	include/rcscripts/rcutil.h            \
 	include/rcscripts/util/str_list.h     \
diff --git a/libsbutil/sb_backtrace.c b/libsbutil/sb_backtrace.c
new file mode 100644
index 0000000..e3d1ed7
--- /dev/null
+++ b/libsbutil/sb_backtrace.c
@@ -0,0 +1,15 @@
+/*
+ * sb_backtrace.c
+ *
+ * Need to keep in a dedicated file so libsandbox can override.
+ *
+ * Copyright 1999-2012 Gentoo Foundation
+ * Licensed under the GPL-2
+ */
+
+#include "headers.h"
+#include "sbutil.h"
+
+void __sb_dump_backtrace(void)
+{
+}
diff --git a/libsbutil/sb_efuncs.c b/libsbutil/sb_efuncs.c
new file mode 100644
index 0000000..248c2bd
--- /dev/null
+++ b/libsbutil/sb_efuncs.c
@@ -0,0 +1,190 @@
+/*
+ * sb_efuncs.c
+ *
+ * Helpers for doing pretty output.
+ *
+ * Copyright 1999-2012 Gentoo Foundation
+ * Licensed under the GPL-2
+ */
+
+#include "headers.h"
+#include "sbutil.h"
+
+static bool nocolor, init_color = false;
+void sb_efunc(const char *color, const char *hilight, const char *format, ...)
+{
+	save_errno();
+
+	int fd = STDERR_FILENO;
+
+	if (!init_color) {
+		nocolor = is_env_on(ENV_NOCOLOR);
+		init_color = true;
+	}
+
+	if (!nocolor)
+		sb_fdprintf(fd, "%s%s%s", color, hilight, COLOR_NORMAL);
+	else
+		sb_fdprintf(fd, "%s", hilight);
+
+	va_list args;
+	va_start(args, format);
+	sb_vfdprintf(fd, format, args);
+	va_end(args);
+
+	restore_errno();
+}
+
+const char *colors[] = {
+	"\033[0m",
+	"\033[32;01m",
+	"\033[33;01m",
+	"\033[31;01m",
+};
+__attribute__((constructor))
+static void sbio_init(void)
+{
+	if (is_env_on(ENV_NOCOLOR))
+		memset(colors, 0, sizeof(colors));
+}
+
+static bool try_portage_helpers = false;
+
+/*
+ * First try to use the helper programs from portage so that it can sanely
+ * log things itself, and so the output doesn't get consumed by something
+ * else #278761.  If that fails, fall back to writing to /dev/tty.  While
+ * this might annoy some people, using stderr will break tests that try to
+ * validate output #261957.
+ */
+static void sb_vefunc(const char *prog, const char *color, const char *format, va_list args)
+{
+	char shellcode[128];
+	FILE *fp;
+	sighandler_t oldsig;
+	bool is_pipe = false;
+
+	if (try_portage_helpers) {
+		/* If popen() fails, then writes to it will trigger SIGPIPE */
+		/* XXX: convert this to sigaction */
+		oldsig = signal(SIGPIPE, SIG_IGN);
+
+		sprintf(shellcode, "xargs %s 2>/dev/null", prog);
+		fp = sbio_popen(shellcode, "we");
+		is_pipe = true;
+	} else
+		fp = NULL;
+
+	if (!fp) {
+ do_tty:
+		is_pipe = false;
+		int fd = sbio_open(sbio_fallback_path, O_WRONLY|O_CLOEXEC, 0);
+		if (fd >= 0)
+			fp = fdopen(fd, "ae");
+		if (!fp)
+			fp = stderr;
+	}
+
+	sb_fprintf(fp, " %s*%s ", color, COLOR_NORMAL);
+	sb_vfprintf(fp, format, args);
+
+	if (is_pipe) {
+		int status = pclose(fp);
+		if (WEXITSTATUS(status))
+			goto do_tty;
+	} else if (fp != stderr)
+		fclose(fp);
+
+	if (try_portage_helpers)
+		signal(SIGPIPE, oldsig);
+}
+
+void sb_einfo(const char *format, ...)
+{
+	va_list args;
+	va_start(args, format);
+	sb_vefunc("einfo", COLOR_GREEN, format, args);
+	va_end(args);
+}
+
+void sb_debug_dyn(const char *format, ...)
+{
+	if (!is_env_on(ENV_SANDBOX_DEBUG))
+		return;
+
+	va_list args;
+	va_start(args, format);
+	sb_vefunc("einfo", COLOR_GREEN, format, args);
+	va_end(args);
+}
+
+void sb_ewarn(const char *format, ...)
+{
+	va_list args;
+	va_start(args, format);
+	sb_vefunc("ewarn", COLOR_YELLOW, format, args);
+	va_end(args);
+}
+
+void sb_eerror(const char *format, ...)
+{
+	va_list args;
+	va_start(args, format);
+	sb_vefunc("eerror", COLOR_RED, format, args);
+	va_end(args);
+}
+
+void sb_eqawarn(const char *format, ...)
+{
+	va_list args;
+	va_start(args, format);
+	sb_vefunc("eqawarn", COLOR_YELLOW, format, args);
+	va_end(args);
+}
+
+void sb_dump_backtrace(void)
+{
+#ifdef HAVE_BACKTRACE
+	void *funcs[10];
+	int num_funcs;
+	num_funcs = backtrace(funcs, ARRAY_SIZE(funcs));
+	backtrace_symbols_fd(funcs, num_funcs, STDERR_FILENO);
+#endif
+	__sb_dump_backtrace();
+}
+
+void __sb_ebort(const char *file, const char *func, size_t line_num, const char *format, ...)
+{
+	va_list args;
+
+	sb_eerror("%s:%s():%zu: failure (%s):\n", file, func, line_num, strerror(errno));
+
+	va_start(args, format);
+	sb_vefunc("eerror", COLOR_RED, format, args);
+	va_end(args);
+
+	sb_dump_backtrace();
+
+#ifndef NDEBUG
+	if (is_env_on("SANDBOX_GDB")) {
+		sb_einfo("attempting to autolaunch gdb; please wait ...\n\n");
+		pid_t crashed_pid = getpid();
+		switch (fork()) {
+			case -1: break;
+			case 0: {
+				char pid[10];
+				snprintf(pid, sizeof(pid), "%i", crashed_pid);
+				unsetenv(ENV_LD_PRELOAD);
+				/*sb_unwrapped_*/execlp("gdb", "gdb", "--quiet", "--pid", pid, "-ex", "bt full", NULL);
+				break;
+			}
+			default: {
+				int status;
+				wait(&status);
+			}
+		}
+	}
+#endif
+
+	abort();
+}
diff --git a/libsbutil/sb_memory.c b/libsbutil/sb_memory.c
index 40a4762..bdc054f 100644
--- a/libsbutil/sb_memory.c
+++ b/libsbutil/sb_memory.c
@@ -1,5 +1,5 @@
 /*
- * debug.c
+ * sb_memory.c
  *
  * Simle debugging/logging macro's and functions.
  *
@@ -16,11 +16,8 @@ __xcalloc(size_t nmemb, size_t size, const char *file, const char *func, size_t
 {
 	void *ret = calloc(nmemb, size);
 
-	if (ret == NULL) {
-		SB_EERROR("calloc()", " %s:%s():%zu: calloc(%zu, %zu) failed: %s\n",
-			file, func, line, nmemb, size, strerror(errno));
-		abort();
-	}
+	if (ret == NULL)
+		__sb_ebort(file, func, line, "calloc(%zu, %zu)\n", nmemb, size);
 
 	return ret;
 }
@@ -30,11 +27,8 @@ __xmalloc(size_t size, const char *file, const char *func, size_t line)
 {
 	void *ret = malloc(size);
 
-	if (ret == NULL) {
-		SB_EERROR("malloc()", " %s:%s():%zu: malloc(%zu) failed: %s\n",
-			file, func, line, size, strerror(errno));
-		abort();
-	}
+	if (ret == NULL)
+		__sb_ebort(file, func, line, "malloc(%zu)\n", size);
 
 	return ret;
 }
@@ -50,11 +44,8 @@ __xrealloc(void *ptr, size_t size, const char *file, const char *func, size_t li
 {
 	void *ret = realloc(ptr, size);
 
-	if (ret == NULL) {
-		SB_EERROR("realloc()", " %s:%s():%zu: realloc(%p, %zu) failed: %s\n",
-			file, func, line, ptr, size, strerror(errno));
-		abort();
-	}
+	if (ret == NULL)
+		__sb_ebort(file, func, line, "realloc(%p, %zu)\n", ptr, size);
 
 	return ret;
 }
@@ -64,11 +55,8 @@ __xstrdup(const char *str, const char *file, const char *func, size_t line)
 {
 	char *ret = strdup(str);
 
-	if (ret == NULL) {
-		SB_EERROR("strdup()", " %s:%s():%zu: strdup(%p) failed: %s\n",
-			file, func, line, str, strerror(errno));
-		abort();
-	}
+	if (ret == NULL)
+		__sb_ebort(file, func, line, "strdup(%p)\n", str);
 
 	return ret;
 }
@@ -94,11 +82,8 @@ __xstrndup(const char *str, size_t size, const char *file, const char *func, siz
 {
 	char *ret = strndup(str, size);
 
-	if (ret == NULL) {
-		SB_EERROR("strndup()", " %s:%s():%zu: strndup(%p, %zu) failed: %s\n",
-			file, func, line, str, size, strerror(errno));
-		abort();
-	}
+	if (ret == NULL)
+		__sb_ebort(file, func, line, "strndup(%p, %zu)\n", str, size);
 
 	return ret;
 }
diff --git a/libsbutil/sb_printf.c b/libsbutil/sb_printf.c
index d3a27df..1ad9e23 100644
--- a/libsbutil/sb_printf.c
+++ b/libsbutil/sb_printf.c
@@ -187,28 +187,3 @@ void sb_printf(const char *format, ...)
 	sb_vfdprintf(STDERR_FILENO, format, args);
 	va_end(args);
 }
-
-static bool nocolor, init_color = false;
-void sb_efunc(const char *color, const char *hilight, const char *format, ...)
-{
-	save_errno();
-
-	int fd = STDERR_FILENO;
-
-	if (!init_color) {
-		nocolor = is_env_on(ENV_NOCOLOR);
-		init_color = true;
-	}
-
-	if (!nocolor)
-		sb_fdprintf(fd, "%s%s%s", color, hilight, COLOR_NORMAL);
-	else
-		sb_fdprintf(fd, "%s", hilight);
-
-	va_list args;
-	va_start(args, format);
-	sb_vfdprintf(fd, format, args);
-	va_end(args);
-
-	restore_errno();
-}
diff --git a/libsbutil/sb_proc.c b/libsbutil/sb_proc.c
new file mode 100644
index 0000000..c583d95
--- /dev/null
+++ b/libsbutil/sb_proc.c
@@ -0,0 +1,31 @@
+/*
+ * funcs for poking around /proc
+ *
+ * Copyright 1999-2012 Gentoo Foundation
+ * Licensed under the GPL-2
+ */
+
+#include "headers.h"
+#include "sbutil.h"
+
+const char sb_fd_dir[] =
+#if defined(SANDBOX_PROC_SELF_FD)
+	"/proc/self/fd"
+#elif defined(SANDBOX_DEV_FD)
+	"/dev/fd"
+#else
+# error "how do i access a proc's fd/ tree ?"
+#endif
+;
+
+const char *sb_get_cmdline(pid_t pid)
+{
+#if !defined(SANDBOX_PROC_1_CMDLINE) && !defined(SANDBOX_PROC_SELF_CMDLINE) && !defined(SANDBOX_PROC_dd_CMDLINE)
+# error "how do i access a proc's cmdline ?"
+#endif
+	static char path[256];
+	if (!pid)
+		pid = getpid();
+	sprintf(path, "/proc/%i/cmdline", pid);
+	return path;
+}
diff --git a/libsbutil/sb_write_fd.c b/libsbutil/sb_write_fd.c
new file mode 100644
index 0000000..f19d7de
--- /dev/null
+++ b/libsbutil/sb_write_fd.c
@@ -0,0 +1,42 @@
+/*
+ * helper for sucking up a file and writing it to a fd.
+ * good for copying the contents of small status files
+ * into a log file.
+ *
+ * Copyright 1999-2012 Gentoo Foundation
+ * Licensed under the GPL-2
+ */
+
+#include "headers.h"
+#include "sbutil.h"
+
+int sb_copy_file_to_fd(const char *file, int ofd)
+{
+	int ret = -1;
+
+	int ifd = sb_open(file, O_RDONLY|O_CLOEXEC, 0);
+	if (ifd == -1)
+		return ret;
+
+	size_t pagesz = getpagesize();
+	char *buf = xmalloc(pagesz);
+	while (1) {
+		size_t len = sb_read(ifd, buf, pagesz);
+		if (len == -1)
+			goto error;
+		else if (!len)
+			break;
+		size_t i;
+		for (i = 0; i < len; ++i)
+			if (!buf[i])
+				buf[i] = ' ';
+		if (sb_write(ofd, buf, len) != len)
+			goto error;
+	}
+
+	ret = 0;
+ error:
+	sb_close(ifd);
+	free(buf);
+	return ret;
+}
diff --git a/libsbutil/sbutil.h b/libsbutil/sbutil.h
index f45402e..f275514 100644
--- a/libsbutil/sbutil.h
+++ b/libsbutil/sbutil.h
@@ -42,8 +42,7 @@
 #define ENV_SANDBOX_VERBOSE    "SANDBOX_VERBOSE"
 #define ENV_SANDBOX_DEBUG      "SANDBOX_DEBUG"
 
-extern const char env_sandbox_testing[];
-#define ENV_SANDBOX_TESTING    env_sandbox_testing
+#define ENV_SANDBOX_TESTING    "__SANDBOX_TESTING"
 
 #define ENV_SANDBOX_LIB        "SANDBOX_LIB"
 #define ENV_SANDBOX_BASHRC     "SANDBOX_BASHRC"
@@ -67,15 +66,11 @@ extern const char env_sandbox_testing[];
 
 #define SB_BUF_LEN             2048
 
-#define COLOR_NORMAL           "\033[0m"
-#define COLOR_GREEN            "\033[32;01m"
-#define COLOR_YELLOW           "\033[33;01m"
-#define COLOR_RED              "\033[31;01m"
-
-/* Gentoo style e* printing macro's */
-#define SB_EINFO(_hilight, _args...) sb_efunc(COLOR_GREEN, _hilight, _args)
-#define SB_EWARN(_hilight, _args...) sb_efunc(COLOR_YELLOW, _hilight, _args)
-#define SB_EERROR(_hilight, _args...) sb_efunc(COLOR_RED, _hilight, _args)
+extern const char *colors[];
+#define COLOR_NORMAL           colors[0]
+#define COLOR_GREEN            colors[1]
+#define COLOR_YELLOW           colors[2]
+#define COLOR_RED              colors[3]
 
 char *get_sandbox_conf(void);
 char *get_sandbox_confd(char *path);
@@ -87,19 +82,41 @@ int get_tmp_dir(char *path);
 bool is_env_on (const char *);
 bool is_env_off (const char *);
 
+/* proc helpers */
+extern const char sb_fd_dir[];
+#define sb_get_fd_dir() sb_fd_dir
+const char *sb_get_cmdline(pid_t pid);
+
 /* libsandbox need to use a wrapper for open */
 attribute_hidden extern int (*sbio_open)(const char *, int, mode_t);
+attribute_hidden extern FILE *(*sbio_popen)(const char *, const char *);
+extern const char sbio_fallback_path[];
 /* Convenience functions to reliably open, read and write to a file */
 int sb_open(const char *path, int flags, mode_t mode);
 size_t sb_read(int fd, void *buf, size_t count);
 size_t sb_write(int fd, const void *buf, size_t count);
 int sb_close(int fd);
+int sb_copy_file_to_fd(const char *file, int ofd);
 
 /* Reliable output */
 __printf(1, 2) void sb_printf(const char *format, ...);
 __printf(2, 3) void sb_fdprintf(int fd, const char *format, ...);
 __printf(2, 0) void sb_vfdprintf(int fd, const char *format, va_list args);
 __printf(3, 4) void sb_efunc(const char *color, const char *hilight, const char *format, ...);
+__printf(1, 2) void sb_einfo(const char *format, ...);
+__printf(1, 2) void sb_ewarn(const char *format, ...);
+__printf(1, 2) void sb_eerror(const char *format, ...);
+__printf(1, 2) void sb_eqawarn(const char *format, ...);
+__printf(1, 2) void sb_debug_dyn(const char *format, ...);
+__printf(4, 5) void __sb_ebort(const char *file, const char *func, size_t line_num, const char *format, ...) __noreturn;
+#define sb_ebort(format, ...) __sb_ebort(__FILE__, __func__, __LINE__, format, ## __VA_ARGS__)
+void sb_dump_backtrace(void);
+void __sb_dump_backtrace(void);
+#define sb_assert(cond) \
+	do { \
+		if (!(cond)) \
+			sb_ebort("assertion failure !(%s)\n", #cond); \
+	} while (0)
 #define sb_fprintf(fp, ...) sb_fdprintf(fileno(fp), __VA_ARGS__)
 #define sb_vfprintf(fp, ...) sb_vfdprintf(fileno(fp), __VA_ARGS__)