libbb: use improved xmalloc_read() from modprobe-small

who: fix compile breakage on some systems
modprobe-small: improve Config help text wording

1 files changed, 56 insertions, 76 deletions

diff --git a/libbb/read.c b/libbb/read.c
index 405e216dc..e67bbfb7e 100644
--- a/libbb/read.c
+++ b/libbb/read.c
@@ -106,7 +106,7 @@ ssize_t FAST_FUNC full_read(int fd, void *buf, size_t len)
         return total;
 }
 
-// Die with an error message if we can't read the entire buffer.
+/* Die with an error message if we can't read the entire buffer. */
 void FAST_FUNC xread(int fd, void *buf, size_t count)
 {
         if (count) {
@@ -116,7 +116,7 @@ void FAST_FUNC xread(int fd, void *buf, size_t count)
         }
 }
 
-// Die with an error message if we can't read one character.
+/* Die with an error message if we can't read one character. */
 unsigned char FAST_FUNC xread_char(int fd)
 {
         char tmp;
@@ -124,7 +124,7 @@ unsigned char FAST_FUNC xread_char(int fd)
         return tmp;
 }
 
-// Read one line a-la fgets. Works only on seekable streams
+/* Read one line a-la fgets. Works only on seekable streams */
 char* FAST_FUNC reads(int fd, char *buffer, size_t size)
 {
         char *p;
@@ -140,9 +140,9 @@ char* FAST_FUNC reads(int fd, char *buffer, size_t size)
         if (p) {
                 off_t offset;
                 *p++ = '\0';
-                // avoid incorrect (unsigned) widening
+                /* avoid incorrect (unsigned) widening */
                 offset = (off_t)(p - buffer) - (off_t)size;
-                // set fd position right after '\n'
+                /* set fd position right after '\n' */
                 if (offset && lseek(fd, offset, SEEK_CUR) == (off_t)-1)
                         return NULL;
         }
@@ -203,39 +203,52 @@ ssize_t FAST_FUNC open_read_close(const char *filename, void *buf, size_t size)
         return read_close(fd, buf, size);
 }
 
+
 // Read (potentially big) files in one go. File size is estimated
-// by stat.
-void* FAST_FUNC xmalloc_open_read_close(const char *filename, size_t *sizep)
+// by stat. Extra '\0' byte is appended.
+void* FAST_FUNC xmalloc_read(int fd, size_t *sizep)
 {
         char *buf;
-        size_t size;
-        int fd;
-        off_t len;
+        size_t size, rd_size, total;
+        off_t to_read;
         struct stat st;
 
-        fd = open(filename, O_RDONLY);
-        if (fd < 0)
-                return NULL;
+        to_read = sizep ? *sizep : MAXINT(ssize_t); /* max to read */
 
-        st.st_size = 0; /* in case fstat fail, define to 0 */
+        /* Estimate file size */
+        st.st_size = 0; /* in case fstat fails, assume 0 */
         fstat(fd, &st);
-        /* /proc/N/stat files report len 0 here */
+        /* /proc/N/stat files report st_size 0 */
         /* In order to make such files readable, we add small const */
-        len = st.st_size | 0x3ff; /* read only 1k on unseekable files */
-        size = sizep ? *sizep : INT_MAX;
-        if (len < size)
-                size = len;
-        buf = xmalloc(size + 1);
-        size = read_close(fd, buf, size);
-        if ((ssize_t)size < 0) {
-                free(buf);
-                return NULL;
+        size = (st.st_size | 0x3ff) + 1;
+
+        total = 0;
+        buf = NULL;
+        while (1) {
+                if (to_read < size)
+                        size = to_read;
+                buf = xrealloc(buf, total + size + 1);
+                rd_size = full_read(fd, buf + total, size);
+                if ((ssize_t)rd_size < 0) { /* error */
+                        free(buf);
+                        return NULL;
+                }
+                total += rd_size;
+                if (rd_size < size) /* EOF */
+                        break;
+                to_read -= rd_size;
+                if (to_read <= 0)
+                        break;
+                /* grow by 1/8, but in [1k..64k] bounds */
+                size = ((total / 8) | 0x3ff) + 1;
+                if (size > 64*1024)
+                        size = 64*1024;
         }
-        xrealloc(buf, size + 1);
-        buf[size] = '\0';
+        xrealloc(buf, total + 1);
+        buf[total] = '\0';
 
         if (sizep)
-                *sizep = size;
+                *sizep = total;
         return buf;
 }
 
@@ -284,59 +297,26 @@ void* FAST_FUNC xmalloc_open_read_close(const char *filename, size_t *sizep)
 }
 #endif
 
-void* FAST_FUNC xmalloc_xopen_read_close(const char *filename, size_t *sizep)
-{
-        void *buf = xmalloc_open_read_close(filename, sizep);
-        if (!buf)
-                bb_perror_msg_and_die("can't read '%s'", filename);
-        return buf;
-}
-
-/* libbb candidate */
-#if 0
-static void *xmalloc_read(int fd, size_t *sizep)
+// Read (potentially big) files in one go. File size is estimated
+// by stat.
+void* FAST_FUNC xmalloc_open_read_close(const char *filename, size_t *sizep)
 {
         char *buf;
-        size_t size, rd_size, total;
-        off_t to_read;
-        struct stat st;
-
-        to_read = sizep ? *sizep : INT_MAX; /* max to read */
+        int fd;
 
-        /* Estimate file size */
-        st.st_size = 0; /* in case fstat fails, assume 0 */
-        fstat(fd, &st);
-        /* /proc/N/stat files report st_size 0 */
-        /* In order to make such files readable, we add small const */
-        size = (st.st_size | 0x3ff) + 1;
+        fd = open(filename, O_RDONLY);
+        if (fd < 0)
+                return NULL;
 
-        total = 0;
-        buf = NULL;
-        while (1) {
-                if (to_read < size)
-                        size = to_read;
-                buf = xrealloc(buf, total + size + 1);
-                rd_size = full_read(fd, buf + total, size);
-                if ((ssize_t)rd_size < 0) { /* error */
-                        free(buf);
-                        return NULL;
-                }
-                total += rd_size;
-                if (rd_size < size) /* EOF */
-                        break;
-                to_read -= rd_size;
-                if (to_read <= 0)
-                        break;
-                /* grow by 1/8, but in [1k..64k] bounds */
-                size = ((total / 8) | 0x3ff) + 1;
-                if (size > 64*1024)
-                        size = 64*1024;
-        }
-        xrealloc(buf, total + 1);
-        buf[total] = '\0';
+        buf = xmalloc_read(fd, sizep);
+        close(fd);
+        return buf;
+}
 
-        if (sizep)
-                *sizep = total;
+void* FAST_FUNC xmalloc_xopen_read_close(const char *filename, size_t *sizep)
+{
+        void *buf = xmalloc_open_read_close(filename, sizep);
+        if (!buf)
+                bb_perror_msg_and_die("can't read '%s'", filename);
         return buf;
 }
-#endif