bsdiff: convert ebuild to the new eclass format

dev-util/bsdiff/files/4.3_bspatch-support-input-output-positioning.patch

+From f8c00fab208cb07e46bc3cb7f651cead857adf07 Mon Sep 17 00:00:00 2001
+From: Andrew de los Reyes <adlr@chromium.org>
+Date: Mon, 19 Apr 2010 15:05:56 -0700
+Subject: [PATCH] bspatch: support input/output positioning
+
+For autoupdate, we need bspatch to read specific blocks from the
+filesystem devic and write back to specific blocks of the device.
+
+Review URL: http://codereview.chromium.org/1595025
+---
+ files/bspatch.c |  270 ++++++++++++++++++++++++++++++++++++++++++++++++++++---
+ 1 files changed, 259 insertions(+), 11 deletions(-)
+
+diff --git a/files/bspatch.c b/files/bspatch.c
+index f4b821c..48ac79a 100644
+--- a/files/bspatch.c
++++ b/files/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 @@ __FBSDID("$FreeBSD: src/usr.bin/bsdiff/bspatch/bspatch.c,v 1.1 2005/08/06 01:59:
+ #endif
+ 
+ #include <bzlib.h>
++#include <errno.h>
++#include <inttypes.h>
++#include <stdint.h>
+ #include <stdlib.h>
+ #include <stdio.h>
+ #include <string.h>
+@@ -36,6 +39,235 @@ __FBSDID("$FreeBSD: src/usr.bin/bsdiff/bspatch/bspatch.c,v 1.1 2005/08/06 01:59:
+ #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 @@ int main(int argc,char * argv[])
+        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 @@ int main(int argc,char * argv[])
+        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 @@ int main(int argc,char * argv[])
+                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);
+-- 
+1.6.4.4
+