Check all lseek calls succeed.

Also add missing TEMP_FAILURE_RETRYs on read, write, and lseek.

Bug: http://b/20625546
Change-Id: I03b198e11c1921b35518ee2dd005a7cfcf4fd94b
(cherry picked from commit 7bad7c4646ee8fd8d6e6ed0ffd3ddbb0c1b41a2f)

14 files changed, 112 insertions, 128 deletions

diff --git a/adb_install.cpp b/adb_install.cpp
index ebd4cac..e3b94ea 100644
--- a/adb_install.cpp
+++ b/adb_install.cpp
@@ -42,7 +42,7 @@ set_usb_driver(bool enabled) {
         ui->Print("failed to open driver control: %s\n", strerror(errno));
         return;
     }
-    if (write(fd, enabled ? "1" : "0", 1) < 0) {
+    if (TEMP_FAILURE_RETRY(write(fd, enabled ? "1" : "0", 1)) == -1) {
         ui->Print("failed to set driver control: %s\n", strerror(errno));
     }
     if (close(fd) < 0) {
diff --git a/applypatch/applypatch.c b/applypatch/applypatch.c
index 2c86e09..6f02a38 100644
--- a/applypatch/applypatch.c
+++ b/applypatch/applypatch.c
@@ -422,20 +422,19 @@ int WriteToPartition(unsigned char* data, size_t len,
             int attempt;
 
             for (attempt = 0; attempt < 2; ++attempt) {
-                lseek(fd, start, SEEK_SET);
+                if (TEMP_FAILURE_RETRY(lseek(fd, start, SEEK_SET)) == -1) {
+                    printf("failed seek on %s: %s\n",
+                           partition, strerror(errno));
+                    return -1;
+                }
                 while (start < len) {
                     size_t to_write = len - start;
                     if (to_write > 1<<20) to_write = 1<<20;
 
-                    ssize_t written = write(fd, data+start, to_write);
-                    if (written < 0) {
-                        if (errno == EINTR) {
-                            written = 0;
-                        } else {
-                            printf("failed write writing to %s (%s)\n",
-                                   partition, strerror(errno));
-                            return -1;
-                        }
+                    ssize_t written = TEMP_FAILURE_RETRY(write(fd, data+start, to_write));
+                    if (written == -1) {
+                        printf("failed write writing to %s: %s\n", partition, strerror(errno));
+                        return -1;
                     }
                     start += written;
                 }
@@ -460,13 +459,20 @@ int WriteToPartition(unsigned char* data, size_t len,
                 // won't just be reading the cache.
                 sync();
                 int dc = open("/proc/sys/vm/drop_caches", O_WRONLY);
-                write(dc, "3\n", 2);
+                if (TEMP_FAILURE_RETRY(write(dc, "3\n", 2)) == -1) {
+                    printf("write to /proc/sys/vm/drop_caches failed: %s\n", strerror(errno));
+                } else {
+                    printf("  caches dropped\n");
+                }
                 close(dc);
                 sleep(1);
-                printf("  caches dropped\n");
 
                 // verify
-                lseek(fd, 0, SEEK_SET);
+                if (TEMP_FAILURE_RETRY(lseek(fd, 0, SEEK_SET)) == -1) {
+                    printf("failed to seek back to beginning of %s: %s\n",
+                           partition, strerror(errno));
+                    return -1;
+                }
                 unsigned char buffer[4096];
                 start = len;
                 size_t p;
@@ -476,15 +482,12 @@ int WriteToPartition(unsigned char* data, size_t len,
 
                     size_t so_far = 0;
                     while (so_far < to_read) {
-                        ssize_t read_count = read(fd, buffer+so_far, to_read-so_far);
-                        if (read_count < 0) {
-                            if (errno == EINTR) {
-                                read_count = 0;
-                            } else {
-                                printf("verify read error %s at %zu: %s\n",
-                                       partition, p, strerror(errno));
-                                return -1;
-                            }
+                        ssize_t read_count =
+                                TEMP_FAILURE_RETRY(read(fd, buffer+so_far, to_read-so_far));
+                        if (read_count == -1) {
+                            printf("verify read error %s at %zu: %s\n",
+                                   partition, p, strerror(errno));
+                            return -1;
                         }
                         if ((size_t)read_count < to_read) {
                             printf("short verify read %s at %zu: %zd %zu %s\n",
@@ -625,8 +628,8 @@ ssize_t FileSink(const unsigned char* data, ssize_t len, void* token) {
     ssize_t done = 0;
     ssize_t wrote;
     while (done < (ssize_t) len) {
-        wrote = write(fd, data+done, len-done);
-        if (wrote <= 0) {
+        wrote = TEMP_FAILURE_RETRY(write(fd, data+done, len-done));
+        if (wrote == -1) {
             printf("error writing %d bytes: %s\n", (int)(len-done), strerror(errno));
             return done;
         }
diff --git a/fuse_sdcard_provider.c b/fuse_sdcard_provider.c
index ca8c914..4565c7b 100644
--- a/fuse_sdcard_provider.c
+++ b/fuse_sdcard_provider.c
@@ -36,19 +36,17 @@ struct file_data {
 static int read_block_file(void* cookie, uint32_t block, uint8_t* buffer, uint32_t fetch_size) {
     struct file_data* fd = (struct file_data*)cookie;
 
-    if (lseek(fd->fd, block * fd->block_size, SEEK_SET) < 0) {
-        printf("seek on sdcard failed: %s\n", strerror(errno));
+    off64_t offset = ((off64_t) block) * fd->block_size;
+    if (TEMP_FAILURE_RETRY(lseek64(fd->fd, offset, SEEK_SET)) == -1) {
+        fprintf(stderr, "seek on sdcard failed: %s\n", strerror(errno));
         return -EIO;
     }
 
     while (fetch_size > 0) {
-        ssize_t r = read(fd->fd, buffer, fetch_size);
-        if (r < 0) {
-            if (r != -EINTR) {
-                printf("read on sdcard failed: %s\n", strerror(errno));
-                return -EIO;
-            }
-            r = 0;
+        ssize_t r = TEMP_FAILURE_RETRY(read(fd->fd, buffer, fetch_size));
+        if (r == -1) {
+            fprintf(stderr, "read on sdcard failed: %s\n", strerror(errno));
+            return -EIO;
         }
         fetch_size -= r;
         buffer += r;
diff --git a/fuse_sideload.c b/fuse_sideload.c
index 1dd84e9..48e6cc5 100644
--- a/fuse_sideload.c
+++ b/fuse_sideload.c
@@ -442,14 +442,12 @@ int run_fuse_sideload(struct provider_vtab* vtab, void* cookie,
     }
     uint8_t request_buffer[sizeof(struct fuse_in_header) + PATH_MAX*8];
     for (;;) {
-        ssize_t len = read(fd.ffd, request_buffer, sizeof(request_buffer));
-        if (len < 0) {
-            if (errno != EINTR) {
-                perror("read request");
-                if (errno == ENODEV) {
-                    result = -1;
-                    break;
-                }
+        ssize_t len = TEMP_FAILURE_RETRY(read(fd.ffd, request_buffer, sizeof(request_buffer)));
+        if (len == -1) {
+            perror("read request");
+            if (errno == ENODEV) {
+                result = -1;
+                break;
             }
             continue;
         }
@@ -508,7 +506,7 @@ int run_fuse_sideload(struct provider_vtab* vtab, void* cookie,
             outhdr.len = sizeof(outhdr);
             outhdr.error = result;
             outhdr.unique = hdr->unique;
-            write(fd.ffd, &outhdr, sizeof(outhdr));
+            TEMP_FAILURE_RETRY(write(fd.ffd, &outhdr, sizeof(outhdr)));
         }
     }
 
diff --git a/minui/events.cpp b/minui/events.cpp
index 2d47a58..3b2262a 100644
--- a/minui/events.cpp
+++ b/minui/events.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <dirent.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -165,7 +166,7 @@ void ev_dispatch(void) {
 
 int ev_get_input(int fd, uint32_t epevents, input_event* ev) {
     if (epevents & EPOLLIN) {
-        ssize_t r = read(fd, ev, sizeof(*ev));
+        ssize_t r = TEMP_FAILURE_RETRY(read(fd, ev, sizeof(*ev)));
         if (r == sizeof(*ev)) {
             return 0;
         }
diff --git a/minzip/SysUtil.c b/minzip/SysUtil.c
index ac6f5c3..b160c9e 100644
--- a/minzip/SysUtil.c
+++ b/minzip/SysUtil.c
@@ -27,11 +27,13 @@ static int getFileStartAndLength(int fd, off_t *start_, size_t *length_)
     assert(start_ != NULL);
     assert(length_ != NULL);
 
-    start = lseek(fd, 0L, SEEK_CUR);
-    end = lseek(fd, 0L, SEEK_END);
-    (void) lseek(fd, start, SEEK_SET);
+    // TODO: isn't start always 0 for the single call site? just use fstat instead?
 
-    if (start == (off_t) -1 || end == (off_t) -1) {
+    start = TEMP_FAILURE_RETRY(lseek(fd, 0L, SEEK_CUR));
+    end = TEMP_FAILURE_RETRY(lseek(fd, 0L, SEEK_END));
+
+    if (TEMP_FAILURE_RETRY(lseek(fd, start, SEEK_SET)) == -1 ||
+                start == (off_t) -1 || end == (off_t) -1) {
         LOGE("could not determine length of file\n");
         return -1;
     }
diff --git a/minzip/Zip.c b/minzip/Zip.c
index d3ff79b..40712e0 100644
--- a/minzip/Zip.c
+++ b/minzip/Zip.c
@@ -675,13 +675,11 @@ static bool writeProcessFunction(const unsigned char *data, int dataLen,
     }
     ssize_t soFar = 0;
     while (true) {
-        ssize_t n = write(fd, data+soFar, dataLen-soFar);
+        ssize_t n = TEMP_FAILURE_RETRY(write(fd, data+soFar, dataLen-soFar));
         if (n <= 0) {
             LOGE("Error writing %zd bytes from zip file from %p: %s\n",
                  dataLen-soFar, data+soFar, strerror(errno));
-            if (errno != EINTR) {
-              return false;
-            }
+            return false;
         } else if (n > 0) {
             soFar += n;
             if (soFar == dataLen) return true;
diff --git a/mtdutils/flash_image.c b/mtdutils/flash_image.c
index 5657dfc..36ffa13 100644
--- a/mtdutils/flash_image.c
+++ b/mtdutils/flash_image.c
@@ -72,7 +72,7 @@ int main(int argc, char **argv) {
     if (fd < 0) die("error opening %s", argv[2]);
 
     char header[HEADER_SIZE];
-    int headerlen = read(fd, header, sizeof(header));
+    int headerlen = TEMP_FAILURE_RETRY(read(fd, header, sizeof(header)));
     if (headerlen <= 0) die("error reading %s header", argv[2]);
 
     MtdReadContext *in = mtd_read_partition(partition);
@@ -104,7 +104,7 @@ int main(int argc, char **argv) {
     if (wrote != headerlen) die("error writing %s", argv[1]);
 
     int len;
-    while ((len = read(fd, buf, sizeof(buf))) > 0) {
+    while ((len = TEMP_FAILURE_RETRY(read(fd, buf, sizeof(buf)))) > 0) {
         wrote = mtd_write_data(out, buf, len);
         if (wrote != len) die("error writing %s", argv[1]);
     }
@@ -125,13 +125,13 @@ int main(int argc, char **argv) {
     if (mtd_partition_info(partition, NULL, &block_size, NULL))
         die("error getting %s block size", argv[1]);
 
-    if (lseek(fd, headerlen, SEEK_SET) != headerlen)
+    if (TEMP_FAILURE_RETRY(lseek(fd, headerlen, SEEK_SET)) != headerlen)
         die("error rewinding %s", argv[2]);
 
     int left = block_size - headerlen;
     while (left < 0) left += block_size;
     while (left > 0) {
-        len = read(fd, buf, left > (int)sizeof(buf) ? (int)sizeof(buf) : left);
+        len = TEMP_FAILURE_RETRY(read(fd, buf, left > (int)sizeof(buf) ? (int)sizeof(buf) : left));
         if (len <= 0) die("error reading %s", argv[2]);
         if (mtd_write_data(out, buf, len) != len)
             die("error writing %s", argv[1]);
diff --git a/mtdutils/mtdutils.c b/mtdutils/mtdutils.c
index 9a17e38..cc30334 100644
--- a/mtdutils/mtdutils.c
+++ b/mtdutils/mtdutils.c
@@ -108,7 +108,7 @@ mtd_scan_partitions()
     if (fd < 0) {
         goto bail;
     }
-    nbytes = read(fd, buf, sizeof(buf) - 1);
+    nbytes = TEMP_FAILURE_RETRY(read(fd, buf, sizeof(buf) - 1));
     close(fd);
     if (nbytes < 0) {
         goto bail;
@@ -279,12 +279,6 @@ MtdReadContext *mtd_read_partition(const MtdPartition *partition)
     return ctx;
 }
 
-// Seeks to a location in the partition.  Don't mix with reads of
-// anything other than whole blocks; unpredictable things will result.
-void mtd_read_skip_to(const MtdReadContext* ctx, size_t offset) {
-    lseek64(ctx->fd, offset, SEEK_SET);
-}
-
 static int read_block(const MtdPartition *partition, int fd, char *data)
 {
     struct mtd_ecc_stats before, after;
@@ -293,13 +287,18 @@ static int read_block(const MtdPartition *partition, int fd, char *data)
         return -1;
     }
 
-    loff_t pos = lseek64(fd, 0, SEEK_CUR);
+    loff_t pos = TEMP_FAILURE_RETRY(lseek64(fd, 0, SEEK_CUR));
+    if (pos == -1) {
+        printf("mtd: read_block: couldn't SEEK_CUR: %s\n", strerror(errno));
+        return -1;
+    }
 
     ssize_t size = partition->erase_size;
     int mgbb;
 
     while (pos + size <= (int) partition->size) {
-        if (lseek64(fd, pos, SEEK_SET) != pos || read(fd, data, size) != size) {
+        if (TEMP_FAILURE_RETRY(lseek64(fd, pos, SEEK_SET)) != pos ||
+                    TEMP_FAILURE_RETRY(read(fd, data, size)) != size) {
             printf("mtd: read error at 0x%08llx (%s)\n",
                     pos, strerror(errno));
         } else if (ioctl(fd, ECCGETSTATS, &after)) {
@@ -409,8 +408,11 @@ static int write_block(MtdWriteContext *ctx, const char *data)
     const MtdPartition *partition = ctx->partition;
     int fd = ctx->fd;
 
-    off_t pos = lseek(fd, 0, SEEK_CUR);
-    if (pos == (off_t) -1) return 1;
+    off_t pos = TEMP_FAILURE_RETRY(lseek(fd, 0, SEEK_CUR));
+    if (pos == (off_t) -1) {
+        printf("mtd: write_block: couldn't SEEK_CUR: %s\n", strerror(errno));
+        return -1;
+    }
 
     ssize_t size = partition->erase_size;
     while (pos + size <= (int) partition->size) {
@@ -435,15 +437,15 @@ static int write_block(MtdWriteContext *ctx, const char *data)
                         pos, strerror(errno));
                 continue;
             }
-            if (lseek(fd, pos, SEEK_SET) != pos ||
-                write(fd, data, size) != size) {
+            if (TEMP_FAILURE_RETRY(lseek(fd, pos, SEEK_SET)) != pos ||
+                TEMP_FAILURE_RETRY(write(fd, data, size)) != size) {
                 printf("mtd: write error at 0x%08lx (%s)\n",
                         pos, strerror(errno));
             }
 
             char verify[size];
-            if (lseek(fd, pos, SEEK_SET) != pos ||
-                read(fd, verify, size) != size) {
+            if (TEMP_FAILURE_RETRY(lseek(fd, pos, SEEK_SET)) != pos ||
+                TEMP_FAILURE_RETRY(read(fd, verify, size)) != size) {
                 printf("mtd: re-read error at 0x%08lx (%s)\n",
                         pos, strerror(errno));
                 continue;
@@ -512,8 +514,11 @@ off_t mtd_erase_blocks(MtdWriteContext *ctx, int blocks)
         ctx->stored = 0;
     }
 
-    off_t pos = lseek(ctx->fd, 0, SEEK_CUR);
-    if ((off_t) pos == (off_t) -1) return pos;
+    off_t pos = TEMP_FAILURE_RETRY(lseek(ctx->fd, 0, SEEK_CUR));
+    if ((off_t) pos == (off_t) -1) {
+        printf("mtd_erase_blocks: couldn't SEEK_CUR: %s\n", strerror(errno));
+        return -1;
+    }
 
     const int total = (ctx->partition->size - pos) / ctx->partition->erase_size;
     if (blocks < 0) blocks = total;
@@ -554,18 +559,3 @@ int mtd_write_close(MtdWriteContext *ctx)
     free(ctx);
     return r;
 }
-
-/* Return the offset of the first good block at or after pos (which
- * might be pos itself).
- */
-off_t mtd_find_write_start(MtdWriteContext *ctx, off_t pos) {
-    int i;
-    for (i = 0; i < ctx->bad_block_count; ++i) {
-        if (ctx->bad_block_offsets[i] == pos) {
-            pos += ctx->partition->erase_size;
-        } else if (ctx->bad_block_offsets[i] > pos) {
-            return pos;
-        }
-    }
-    return pos;
-}
diff --git a/mtdutils/mtdutils.h b/mtdutils/mtdutils.h
index 2708c43..8059d6a 100644
--- a/mtdutils/mtdutils.h
+++ b/mtdutils/mtdutils.h
@@ -49,12 +49,10 @@ typedef struct MtdWriteContext MtdWriteContext;
 MtdReadContext *mtd_read_partition(const MtdPartition *);
 ssize_t mtd_read_data(MtdReadContext *, char *data, size_t data_len);
 void mtd_read_close(MtdReadContext *);
-void mtd_read_skip_to(const MtdReadContext *, size_t offset);
 
 MtdWriteContext *mtd_write_partition(const MtdPartition *);
 ssize_t mtd_write_data(MtdWriteContext *, const char *data, size_t data_len);
 off_t mtd_erase_blocks(MtdWriteContext *, int blocks);  /* 0 ok, -1 for all */
-off_t mtd_find_write_start(MtdWriteContext *ctx, off_t pos);
 int mtd_write_close(MtdWriteContext *);
 
 #ifdef __cplusplus
diff --git a/tools/ota/check-lost+found.c b/tools/ota/check-lost+found.c
index cbf7926..8ce12d3 100644
--- a/tools/ota/check-lost+found.c
+++ b/tools/ota/check-lost+found.c
@@ -78,7 +78,7 @@ int main(int argc __attribute__((unused)), char **argv __attribute__((unused)))
                 snprintf(fn, sizeof(fn), "%s/%s", kPartitions[i], "dirty");
                 fd = open(fn, O_WRONLY|O_CREAT, 0444);
                 if (fd >= 0) {  // Don't sweat it if we can't write the file.
-                    write(fd, fn, sizeof(fn));  // write, you know, some data
+                    TEMP_FAILURE_RETRY(write(fd, fn, sizeof(fn)));  // write, you know, some data
                     close(fd);
                     unlink(fn);
                 }
diff --git a/ui.cpp b/ui.cpp
index dca325f..1a0b079 100644
--- a/ui.cpp
+++ b/ui.cpp
@@ -251,7 +251,7 @@ bool RecoveryUI::IsUsbConnected() {
 
     char buf;
     // USB is connected if android_usb state is CONNECTED or CONFIGURED.
-    int connected = (read(fd, &buf, 1) == 1) && (buf == 'C');
+    int connected = (TEMP_FAILURE_RETRY(read(fd, &buf, 1)) == 1) && (buf == 'C');
     if (close(fd) < 0) {
         printf("failed to close /sys/class/android_usb/android0/state: %s\n",
                strerror(errno));
diff --git a/uncrypt/uncrypt.c b/uncrypt/uncrypt.c
index aa75210..da035df 100644
--- a/uncrypt/uncrypt.c
+++ b/uncrypt/uncrypt.c
@@ -65,12 +65,15 @@ static struct fstab* fstab = NULL;
 static int write_at_offset(unsigned char* buffer, size_t size,
                            int wfd, off64_t offset)
 {
-    lseek64(wfd, offset, SEEK_SET);
+    if (TEMP_FAILURE_RETRY(lseek64(wfd, offset, SEEK_SET)) == -1) {
+        ALOGE("error seeking to offset %lld: %s\n", offset, strerror(errno));
+        return -1;
+    }
     size_t written = 0;
     while (written < size) {
-        ssize_t wrote = write(wfd, buffer + written, size - written);
-        if (wrote < 0) {
-            ALOGE("error writing offset %lld: %s\n", offset, strerror(errno));
+        ssize_t wrote = TEMP_FAILURE_RETRY(write(wfd, buffer + written, size - written));
+        if (wrote == -1) {
+            ALOGE("error writing offset %lld: %s\n", (offset + written), strerror(errno));
             return -1;
         }
         written += wrote;
@@ -275,8 +278,9 @@ int produce_block_map(const char* path, const char* map_file, const char* blk_de
         if (encrypted) {
             size_t so_far = 0;
             while (so_far < sb.st_blksize && pos < sb.st_size) {
-                ssize_t this_read = read(fd, buffers[tail] + so_far, sb.st_blksize - so_far);
-                if (this_read < 0) {
+                ssize_t this_read =
+                        TEMP_FAILURE_RETRY(read(fd, buffers[tail] + so_far, sb.st_blksize - so_far));
+                if (this_read == -1) {
                     ALOGE("failed to read: %s\n", strerror(errno));
                     return -1;
                 }
@@ -340,8 +344,8 @@ void wipe_misc() {
             size_t written = 0;
             size_t size = sizeof(zeroes);
             while (written < size) {
-                ssize_t w = write(fd, zeroes, size-written);
-                if (w < 0 && errno != EINTR) {
+                ssize_t w = TEMP_FAILURE_RETRY(write(fd, zeroes, size-written));
+                if (w == -1) {
                     ALOGE("zero write failed: %s\n", strerror(errno));
                     return;
                 } else {
diff --git a/updater/blockimg.c b/updater/blockimg.c
index d5344f9..532e7b8 100644
--- a/updater/blockimg.c
+++ b/updater/blockimg.c
@@ -113,13 +113,12 @@ static int range_overlaps(RangeSet* r1, RangeSet* r2) {
 static int read_all(int fd, uint8_t* data, size_t size) {
     size_t so_far = 0;
     while (so_far < size) {
-        ssize_t r = read(fd, data+so_far, size-so_far);
-        if (r < 0 && errno != EINTR) {
+        ssize_t r = TEMP_FAILURE_RETRY(read(fd, data+so_far, size-so_far));
+        if (r == -1) {
             fprintf(stderr, "read failed: %s\n", strerror(errno));
             return -1;
-        } else {
-            so_far += r;
         }
+        so_far += r;
     }
     return 0;
 }
@@ -127,13 +126,12 @@ static int read_all(int fd, uint8_t* data, size_t size) {
 static int write_all(int fd, const uint8_t* data, size_t size) {
     size_t written = 0;
     while (written < size) {
-        ssize_t w = write(fd, data+written, size-written);
-        if (w < 0 && errno != EINTR) {
+        ssize_t w = TEMP_FAILURE_RETRY(write(fd, data+written, size-written));
+        if (w == -1) {
             fprintf(stderr, "write failed: %s\n", strerror(errno));
             return -1;
-        } else {
-            written += w;
         }
+        written += w;
     }
 
     if (fsync(fd) == -1) {
@@ -144,19 +142,13 @@ static int write_all(int fd, const uint8_t* data, size_t size) {
     return 0;
 }
 
-static int check_lseek(int fd, off64_t offset, int whence) {
-    while (true) {
-        off64_t ret = lseek64(fd, offset, whence);
-        if (ret < 0) {
-            if (errno != EINTR) {
-                fprintf(stderr, "lseek64 failed: %s\n", strerror(errno));
-                return -1;
-            }
-        } else {
-            break;
-        }
+static bool check_lseek(int fd, off64_t offset, int whence) {
+    off64_t rc = TEMP_FAILURE_RETRY(lseek64(fd, offset, whence));
+    if (rc == -1) {
+        fprintf(stderr, "lseek64 failed: %s\n", strerror(errno));
+        return false;
     }
-    return 0;
+    return true;
 }
 
 static void allocate(size_t size, uint8_t** buffer, size_t* buffer_alloc) {
@@ -213,8 +205,8 @@ static ssize_t RangeSinkWrite(const uint8_t* data, ssize_t size, void* token) {
                 rss->p_remain = (rss->tgt->pos[rss->p_block * 2 + 1] -
                                  rss->tgt->pos[rss->p_block * 2]) * BLOCKSIZE;
 
-                if (check_lseek(rss->fd, (off64_t)rss->tgt->pos[rss->p_block*2] * BLOCKSIZE,
-                        SEEK_SET) == -1) {
+                if (!check_lseek(rss->fd, (off64_t)rss->tgt->pos[rss->p_block*2] * BLOCKSIZE,
+                                 SEEK_SET)) {
                     break;
                 }
             } else {
@@ -306,7 +298,7 @@ static int ReadBlocks(RangeSet* src, uint8_t* buffer, int fd) {
     }
 
     for (i = 0; i < src->count; ++i) {
-        if (check_lseek(fd, (off64_t) src->pos[i * 2] * BLOCKSIZE, SEEK_SET) == -1) {
+        if (!check_lseek(fd, (off64_t) src->pos[i * 2] * BLOCKSIZE, SEEK_SET)) {
             return -1;
         }
 
@@ -332,7 +324,7 @@ static int WriteBlocks(RangeSet* tgt, uint8_t* buffer, int fd) {
     }
 
     for (i = 0; i < tgt->count; ++i) {
-        if (check_lseek(fd, (off64_t) tgt->pos[i * 2] * BLOCKSIZE, SEEK_SET) == -1) {
+        if (!check_lseek(fd, (off64_t) tgt->pos[i * 2] * BLOCKSIZE, SEEK_SET)) {
             return -1;
         }
 
@@ -1217,7 +1209,7 @@ static int PerformCommandZero(CommandParameters* params) {
 
     if (params->canwrite) {
         for (i = 0; i < tgt->count; ++i) {
-            if (check_lseek(params->fd, (off64_t) tgt->pos[i * 2] * BLOCKSIZE, SEEK_SET) == -1) {
+            if (!check_lseek(params->fd, (off64_t) tgt->pos[i * 2] * BLOCKSIZE, SEEK_SET)) {
                 goto pczout;
             }
 
@@ -1271,7 +1263,7 @@ static int PerformCommandNew(CommandParameters* params) {
         rss.p_block = 0;
         rss.p_remain = (tgt->pos[1] - tgt->pos[0]) * BLOCKSIZE;
 
-        if (check_lseek(params->fd, (off64_t) tgt->pos[0] * BLOCKSIZE, SEEK_SET) == -1) {
+        if (!check_lseek(params->fd, (off64_t) tgt->pos[0] * BLOCKSIZE, SEEK_SET)) {
             goto pcnout;
         }
 
@@ -1367,7 +1359,7 @@ static int PerformCommandDiff(CommandParameters* params) {
             rss.p_block = 0;
             rss.p_remain = (tgt->pos[1] - tgt->pos[0]) * BLOCKSIZE;
 
-            if (check_lseek(params->fd, (off64_t) tgt->pos[0] * BLOCKSIZE, SEEK_SET) == -1) {
+            if (!check_lseek(params->fd, (off64_t) tgt->pos[0] * BLOCKSIZE, SEEK_SET)) {
                 goto pcdout;
             }
 
@@ -1906,7 +1898,7 @@ Value* RangeSha1Fn(const char* name, State* state, int argc, Expr* argv[]) {
 
     int i, j;
     for (i = 0; i < rs->count; ++i) {
-        if (check_lseek(fd, (off64_t)rs->pos[i*2] * BLOCKSIZE, SEEK_SET) == -1) {
+        if (!check_lseek(fd, (off64_t)rs->pos[i*2] * BLOCKSIZE, SEEK_SET)) {
             ErrorAbort(state, "failed to seek %s: %s", blockdev_filename->data,
                 strerror(errno));
             goto done;