bsdiff: convert ebuild to the new eclass format
Portage automatically uses an overlay ebuild of the same name, so it suffices to copy and modify the original ebuild.
Review URL: http://codereview.chromium.org/2779016
diff --git a/bspatch.c b/bspatch.c
index f4b821c..48ac79a 100644
--- a/bspatch.c
+++ b/bspatch.c
@@ -3,7 +3,7 @@
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
- * modification, are permitted providing that the following conditions
+ * modification, are permitted providing that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
@@ -29,6 +29,9 @@
#endif
#include <bzlib.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
@@ -36,6 +39,235 @@
#include <unistd.h>
#include <fcntl.h>
+#define JOIN(a, b) __JOIN(a, b)
+#define __JOIN(a, b) a ## b
+#define COMPILE_ASSERT(expr, message) \
+ typedef char JOIN(message, JOIN(_, __LINE__)) [(expr) ? 1 : -1]
+
+COMPILE_ASSERT(sizeof(int64_t) == 8, int64_t_64_bit);
+
+#define MIN(a, b) \
+ ((a) < (b) ? (a) : (b))
+
+// Reads next int from *ints. The int should be terminated with a comma
+// or NULL char. *ints will be updated to the space right after the comma
+// or set to NULL if this was the last number. This assumes the input is
+// a valid string, as validated with PositionsStringIsValid().
+// Returns 1 on success.
+int NextInt64(const char** ints, int64_t *out) {
+ if (!ints[0])
+ return 0;
+ int r = sscanf(*ints, "%" PRIi64, out);
+ if (r == 1) {
+ const char* next_comma = strchr(*ints, ',');
+ const char* next_colon = strchr(*ints, ':');
+ if (!next_comma && !next_colon)
+ *ints = NULL;
+ else if (!next_comma)
+ *ints = next_colon + 1;
+ else if (!next_colon)
+ *ints = next_comma + 1;
+ else
+ *ints = MIN(next_comma, next_colon) + 1;
+ return 1;
+ }
+ return 0;
+}
+
+COMPILE_ASSERT(sizeof(intmax_t) == 8, intmax_t_not_64_bit);
+
+// Returns 1 if str can be converted to int64_t without over/underflowing.
+// str is assumed to point to an optional negative sign followed by numbers,
+// optionally followed by non-numeric characters, followed by '\0'.
+int IsValidInt64(const char* str) {
+ const char* end_ptr;
+ errno = 0;
+ intmax_t result = strtoimax(str, &end_ptr, /* base: */ 10);
+ return errno == 0;
+}
+
+// Input validator. Make sure the positions string is well formatted.
+// All numerical values are checked to make sure they don't over/underflow
+// int64_t. Returns 1 if valid.
+int PositionsStringIsValid(const char* positions) {
+ if (positions == NULL)
+ errx(1, "bad string");
+
+ // Special case: empty string is valid
+ if (!positions[0])
+ return 1;
+
+ // Use a state machine to determine if the string is valid.
+ // Key: (s): state, ((s)) valid end state.
+ // n (negative_valid) is a boolean that starts out as true.
+ // If n is true, ':' is the delimiter, otherwise ','.
+ //
+ // .--------------------------.
+ // | | n ? ':' : ',' ; n = !n
+ // V '-'&&n 0-9 |
+ // start->(0)------------->(1)----->((2))---.
+ // `---------------------> <--' 0-9
+ // 0-9
+ int state = 0;
+ int negative_valid = 1;
+ const char* number_start = positions;
+ for (;; positions++) {
+ char c = *positions;
+ switch (state) {
+ case 0:
+ if (c == '-' && negative_valid) {
+ state = 1;
+ continue;
+ }
+ if (isdigit(c)) {
+ state = 2;
+ continue;
+ }
+ return 0;
+ case 1:
+ if (isdigit(c)) {
+ state = 2;
+ continue;
+ }
+ return 0;
+ case 2:
+ if (isdigit(c))
+ continue;
+ // number_start must point to a valid number
+ if (!IsValidInt64(number_start)) {
+ return 0;
+ }
+ if ((negative_valid && c == ':') ||
+ (!negative_valid && c == ',')) {
+ state = 0;
+ number_start = positions + 1;
+ negative_valid = !negative_valid;
+ continue;
+ }
+ return (c == '\0');
+ }
+ }
+}
+
+// Reads into a buffer a series of byte ranges from filename.
+// Each range is a pair of comma-separated ints from positions.
+// -1 as an offset means a sparse-hole.
+// E.g. If positions were "1,5:23,4:-1,8:3,7", then we would return a buffer
+// consisting of 5 bytes from offset 1 of the file, followed by
+// 4 bytes from offset 23, then 8 bytes of all zeros, then 7 bytes from
+// offset 3 in the file.
+// Returns NULL on error.
+static char* PositionedRead(const char* filename,
+ const char* positions,
+ ssize_t* old_size) {
+ if (!PositionsStringIsValid(positions)) {
+ errx(1, "invalid positions string for read\n");
+ }
+
+ // Get length
+ const char* p = positions;
+ int64_t length = 0;
+ for (;;) {
+ int64_t value;
+ if (0 == NextInt64(&p, &value)) {
+ break;
+ }
+ int r = NextInt64(&p, &value);
+ if (r == 0) {
+ errx(1, "bad length parse\n");
+ }
+ if (value < 0) {
+ errx(1, "length can't be negative\n");
+ }
+ length += value;
+ }
+
+ // Malloc
+ if (length > 0x40000000) { // 1 GiB; sanity check
+ errx(1, "Read length too long (exceeds 1 GiB)");
+ }
+ // Following bsdiff convention, allocate length + 1 to avoid malloc(0)
+ char* buf = malloc(length + 1);
+ if (buf == NULL) {
+ errx(1, "malloc failed\n");
+ }
+ char* buf_tail = buf;
+
+ int fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ errx(1, "open failed for read\n");
+ }
+
+ // Read bytes
+ p = positions;
+ for (;;) {
+ int64_t offset, read_length;
+ if (NextInt64(&p, &offset) == 0) {
+ break;
+ }
+ if (offset < 0) {
+ errx(1, "no support for sparse positions "
+ "yet during read\n");
+ }
+ if (NextInt64(&p, &read_length) == 0) {
+ errx(1, "bad length parse (should never happen)\n");
+ }
+ if (read_length < 0) {
+ errx(1, "length can't be negative "
+ "(should never happen)\n");
+ }
+ ssize_t rc = pread(fd, buf_tail, read_length, offset);
+ if (rc != read_length) {
+ errx(1, "read failed\n");
+ }
+ buf_tail += rc;
+ }
+ close(fd);
+ *old_size = length;
+ return buf;
+}
+
+static void PositionedWrite(const char* filename,
+ const char* positions,
+ const char* buf,
+ ssize_t new_size) {
+ if (!PositionsStringIsValid(positions)) {
+ errx(1, "invalid positions string for write\n");
+ }
+ int fd = open(filename, O_WRONLY | O_CREAT, 0666);
+ if (fd < 0) {
+ errx(1, "open failed for write\n");
+ }
+
+ for (;;) {
+ int64_t offset, length;
+ if (NextInt64(&positions, &offset) == 0) {
+ break;
+ }
+ if (NextInt64(&positions, &length) == 0) {
+ errx(1, "bad length parse for write\n");
+ }
+ if (length < 0) {
+ errx(1, "length can't be negative for write\n");
+ }
+
+ if (offset < 0) {
+ // Sparse hole. Skip.
+ } else {
+ ssize_t rc = pwrite(fd, buf, length, offset);
+ if (rc != length) {
+ errx(1, "write failed\n");
+ }
+ }
+ buf += length;
+ new_size -= length;
+ }
+ if (new_size != 0) {
+ errx(1, "output position length doesn't match new size\n");
+ }
+ close(fd);
+}
+
static off_t offtin(u_char *buf)
{
off_t y;
@@ -69,7 +301,13 @@
off_t lenread;
off_t i;
- if(argc!=4) errx(1,"usage: %s oldfile newfile patchfile\n",argv[0]);
+ if ((argc != 6) && (argc != 4)) {
+ errx(1,"usage: %s oldfile newfile patchfile \\\n"
+ " [in_offset,in_length,in_offset,in_length,... \\\n"
+ " out_offset,out_length,"
+ "out_offset,out_length,...]\n",argv[0]);
+ }
+ int using_positioning = (argc == 6);
/* Open patch file */
if ((f = fopen(argv[3], "r")) == NULL)
@@ -132,12 +370,18 @@
if ((epfbz2 = BZ2_bzReadOpen(&ebz2err, epf, 0, 0, NULL, 0)) == NULL)
errx(1, "BZ2_bzReadOpen, bz2err = %d", ebz2err);
- if(((fd=open(argv[1],O_RDONLY,0))<0) ||
- ((oldsize=lseek(fd,0,SEEK_END))==-1) ||
- ((old=malloc(oldsize+1))==NULL) ||
- (lseek(fd,0,SEEK_SET)!=0) ||
- (read(fd,old,oldsize)!=oldsize) ||
- (close(fd)==-1)) err(1,"%s",argv[1]);
+ // Read
+
+ if (!using_positioning) {
+ if(((fd=open(argv[1],O_RDONLY,0))<0) ||
+ ((oldsize=lseek(fd,0,SEEK_END))==-1) ||
+ ((old=malloc(oldsize+1))==NULL) ||
+ (lseek(fd,0,SEEK_SET)!=0) ||
+ (read(fd,old,oldsize)!=oldsize) ||
+ (close(fd)==-1)) err(1,"%s",argv[1]);
+ } else {
+ old = PositionedRead(argv[1], argv[4], &oldsize);
+ }
if((new=malloc(newsize+1))==NULL) err(1,NULL);
oldpos=0;newpos=0;
@@ -193,9 +437,13 @@
err(1, "fclose(%s)", argv[3]);
/* Write the new file */
- if(((fd=open(argv[2],O_CREAT|O_TRUNC|O_WRONLY,0666))<0) ||
- (write(fd,new,newsize)!=newsize) || (close(fd)==-1))
- err(1,"%s",argv[2]);
+ if (!using_positioning) {
+ if(((fd=open(argv[2],O_CREAT|O_TRUNC|O_WRONLY,0666))<0) ||
+ (write(fd,new,newsize)!=newsize) || (close(fd)==-1))
+ err(1,"%s",argv[2]);
+ } else {
+ PositionedWrite(argv[2], argv[5], new, newsize);
+ }
free(new);
free(old);
