add open_read_close() and similar stuff

6 files changed, 144 insertions, 103 deletions

diff --git a/libbb/Kbuild b/libbb/Kbuild
index 27ed68c2c..3b16f5c45 100644
--- a/libbb/Kbuild
+++ b/libbb/Kbuild
@@ -9,7 +9,7 @@ lib-y:= \
         compare_string_array.o concat_path_file.o copy_file.o copyfd.o \
         crc32.o create_icmp_socket.o create_icmp6_socket.o \
         device_open.o dump.o error_msg.o error_msg_and_die.o \
-        find_pid_by_name.o find_root_device.o fgets_str.o full_read.o \
+        find_pid_by_name.o find_root_device.o fgets_str.o \
         full_write.o get_last_path_component.o get_line_from_file.o \
         herror_msg.o herror_msg_and_die.o \
         human_readable.o inet_common.o inode_hash.o isdirectory.o \
@@ -19,7 +19,7 @@ lib-y:= \
         perror_msg_and_die.o get_console.o \
         process_escape_sequence.o procps.o \
         recursive_action.o remove_file.o \
-        restricted_shell.o run_parts.o run_shell.o safe_read.o safe_write.o \
+        restricted_shell.o run_parts.o run_shell.o read.o safe_write.o \
         safe_strncpy.o setup_environment.o sha1.o simplify_path.o \
         trim.o u_signal_names.o vdprintf.o verror_msg.o \
         vherror_msg.o vperror_msg.o wfopen.o xconnect.o xgetcwd.o \
diff --git a/libbb/full_read.c b/libbb/full_read.c
deleted file mode 100644
index 068d16698..000000000
--- a/libbb/full_read.c
+++ /dev/null
@@ -1,42 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * Utility routines.
- *
- * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
- *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
- */
-
-#include <stdio.h>
-#include <unistd.h>
-#include "libbb.h"
-
-/*
- * Read all of the supplied buffer from a file.
- * This does multiple reads as necessary.
- * Returns the amount read, or -1 on an error.
- * A short read is returned on an end of file.
- */
-ssize_t full_read(int fd, void *buf, size_t len)
-{
-        ssize_t cc;
-        ssize_t total;
-
-        total = 0;
-
-        while (len) {
-                cc = safe_read(fd, buf, len);
-
-                if (cc < 0)
-                        return cc;      /* read() returns -1 on failure. */
-
-                if (cc == 0)
-                        break;
-
-                buf = ((char *)buf) + cc;
-                total += cc;
-                len -= cc;
-        }
-
-        return total;
-}
diff --git a/libbb/procps.c b/libbb/procps.c
index 2bcd2cced..eba90705c 100644
--- a/libbb/procps.c
+++ b/libbb/procps.c
@@ -22,15 +22,9 @@
 
 static int read_to_buf(const char *filename, void *buf)
 {
-        int fd;
         ssize_t ret;
-
-        fd = open(filename, O_RDONLY);
-        if (fd < 0)
-                return -1;
-        ret = read(fd, buf, PROCPS_BUFSIZE-1);
-        ((char *)buf)[ret > 0 ? ret : 0] = 0;
-        close(fd);
+        ret = open_read_close(filename, buf, PROCPS_BUFSIZE-1);
+        ((char *)buf)[ret > 0 ? ret : 0] = '\0';
         return ret;
 }
 
diff --git a/libbb/read.c b/libbb/read.c
new file mode 100644
index 000000000..1c2945f45
--- /dev/null
+++ b/libbb/read.c
@@ -0,0 +1,133 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include "libbb.h"
+
+ssize_t safe_read(int fd, void *buf, size_t count)
+{
+        ssize_t n;
+
+        do {
+                n = read(fd, buf, count);
+        } while (n < 0 && errno == EINTR);
+
+        return n;
+}
+
+/*
+ * Read all of the supplied buffer from a file.
+ * This does multiple reads as necessary.
+ * Returns the amount read, or -1 on an error.
+ * A short read is returned on an end of file.
+ */
+ssize_t full_read(int fd, void *buf, size_t len)
+{
+        ssize_t cc;
+        ssize_t total;
+
+        total = 0;
+
+        while (len) {
+                cc = safe_read(fd, buf, len);
+
+                if (cc < 0)
+                        return cc;      /* read() returns -1 on failure. */
+
+                if (cc == 0)
+                        break;
+
+                buf = ((char *)buf) + cc;
+                total += cc;
+                len -= cc;
+        }
+
+        return total;
+}
+
+// Die with an error message if we can't read the entire buffer.
+void xread(int fd, void *buf, size_t count)
+{
+        if (count) {
+                ssize_t size = full_read(fd, buf, count);
+                if (size != count)
+                        bb_error_msg_and_die("short read");
+        }
+}
+
+// Die with an error message if we can't read one character.
+unsigned char xread_char(int fd)
+{
+        char tmp;
+
+        xread(fd, &tmp, 1);
+
+        return tmp;
+}
+
+// Read one line a-la fgets. Works only on seekable streams
+char *reads(int fd, char *buffer, size_t size)
+{
+        char *p;
+
+        if (size < 2)
+                return NULL;
+        size = full_read(fd, buffer, size-1);
+        if ((ssize_t)size <= 0)
+                return NULL;
+
+        buffer[size] = '\0';
+        p = strchr(buffer, '\n');
+        if (p) {
+                off_t offset;
+                *p++ = '\0';
+                offset = (p-buffer) - size;
+                // set fd position the right after the \n
+                if (offset && lseek(fd, offset, SEEK_CUR) == (off_t)-1)
+                        return NULL;
+        }
+        return buffer;
+}
+
+ssize_t read_close(int fd, void *buf, size_t size)
+{
+        int e;
+        size = full_read(fd, buf, size);
+        e = errno;
+        close(fd);
+        errno = e;
+        return size;
+}
+
+ssize_t open_read_close(const char *filename, void *buf, size_t size)
+{
+        int fd = open(filename, O_RDONLY);
+        if (fd < 0)
+                return fd;
+        return read_close(fd, buf, size);
+}
+
+void *xmalloc_open_read_close(const char *filename, size_t *sizep)
+{
+        char *buf;
+        size_t size = sizep ? *sizep : INT_MAX;
+        int fd = xopen(filename, O_RDONLY);
+        off_t len = xlseek(fd, 0, SEEK_END);
+        xlseek(fd, 0, SEEK_SET);
+
+        if (len > size)
+                bb_error_msg_and_die("file '%s' is too big", filename);
+        size = len;
+        buf = xmalloc(size+1);
+        size = read_close(fd, buf, size);
+        if ((ssize_t)size < 0)
+                bb_perror_msg_and_die("'%s'", filename);
+        buf[size] = '\0';
+        if (sizep) *sizep = size;
+        return buf;
+}
diff --git a/libbb/safe_read.c b/libbb/safe_read.c
deleted file mode 100644
index a59934a4d..000000000
--- a/libbb/safe_read.c
+++ /dev/null
@@ -1,26 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * Utility routines.
- *
- * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
- *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
- */
-
-#include <stdio.h>
-#include <errno.h>
-#include <unistd.h>
-#include "libbb.h"
-
-
-
-ssize_t safe_read(int fd, void *buf, size_t count)
-{
-        ssize_t n;
-
-        do {
-                n = read(fd, buf, count);
-        } while (n < 0 && errno == EINTR);
-
-        return n;
-}
diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index efc919491..0a5abb878 100644
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -95,7 +95,7 @@ int xopen(const char *pathname, int flags)
         if (ENABLE_DEBUG && (flags & O_CREAT))
                 bb_error_msg_and_die("xopen() with O_CREAT");
 
-        return xopen3(pathname, flags, 0777);
+        return xopen3(pathname, flags, 0666);
 }
 
 // Die if we can't open a new file and return an fd.
@@ -110,16 +110,6 @@ int xopen3(const char *pathname, int flags, int mode)
         return ret;
 }
 
-// Die with an error message if we can't read the entire buffer.
-void xread(int fd, void *buf, size_t count)
-{
-        if (count) {
-                ssize_t size = full_read(fd, buf, count);
-                if (size != count)
-                        bb_error_msg_and_die("short read");
-        }
-}
-
 // Die with an error message if we can't write the entire buffer.
 void xwrite(int fd, void *buf, size_t count)
 {
@@ -131,20 +121,12 @@ void xwrite(int fd, void *buf, size_t count)
 }
 
 // Die with an error message if we can't lseek to the right spot.
-void xlseek(int fd, off_t offset, int whence)
+off_t xlseek(int fd, off_t offset, int whence)
 {
-        if (offset != lseek(fd, offset, whence))
-                bb_error_msg_and_die("lseek");
-}
-
-// Die with an error message if we can't read one character.
-unsigned char xread_char(int fd)
-{
-        char tmp;
-
-        xread(fd, &tmp, 1);
-
-        return tmp;
+        off_t off = lseek(fd, offset, whence);
+        if (off == (off_t)-1)
+                bb_perror_msg_and_die("lseek");
+        return off;
 }
 
 // Die with supplied error message if this FILE * has ferror set.
@@ -309,7 +291,7 @@ off_t fdlength(int fd)
 
                 // If we can read from the current location, it's bigger.
 
-                if (lseek(fd, pos, 0)>=0 && safe_read(fd, &temp, 1)==1) {
+                if (lseek(fd, pos, SEEK_SET)>=0 && safe_read(fd, &temp, 1)==1) {
                         if (bottom == top) bottom = top = (top+1) * 2;
                         else bottom = pos;