Attachment 15382 Details for Bug 14126 – Patch to check some fseek() calls, and check file is seekable on initialization

[patch] Patch to check some fseek() calls, and check file is seekable on initialization

poppler-check-fseek.diff (text/plain), 8.10 KB, created by Ed Avis on 2008-03-21 12:41:31 UTC

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Creator: Ed Avis

Created: 2008-03-21 12:41:31 UTC

Size: 8.10 KB

patch

obsolete

>diff --git a/fofi/FoFiBase.cc b/fofi/FoFiBase.cc
>index ef8992a..52ed27d 100644
>--- a/fofi/FoFiBase.cc
>+++ b/fofi/FoFiBase.cc
>@@ -14,6 +14,7 @@
> 
> #include <stdio.h>
> #include "goo/gmem.h"
>+#include "Error.h"
> #include "FoFiBase.h"
> 
> //------------------------------------------------------------------------
>@@ -38,11 +39,18 @@ char *FoFiBase::readFile(char *fileName, int *fileLen) {
>   int n;
> 
>   if (!(f = fopen(fileName, "rb"))) {
>+    error(-1, "Cannot open '%s'", fileName);
>+    return NULL;
>+  }
>+  if (fseek(f, 0, SEEK_END) != 0) {
>+    error(-1, "Cannot seek to end of file");
>     return NULL;
>   }
>-  fseek(f, 0, SEEK_END);
>   n = (int)ftell(f);
>-  fseek(f, 0, SEEK_SET);
>+  if (fseek(f, 0, SEEK_SET) != 0) {
>+    error(-1, "Cannot seek to start of file");
>+    return NULL;
>+  }
>   buf = (char *)gmalloc(n);
>   if ((int)fread(buf, 1, n, f) != n) {
>     gfree(buf);
>diff --git a/poppler/GfxFont.cc b/poppler/GfxFont.cc
>index 655e259..eeff005 100644
>--- a/poppler/GfxFont.cc
>+++ b/poppler/GfxFont.cc
>@@ -408,9 +408,15 @@ char *GfxFont::readExtFontFile(int *len) {
>     error(-1, "External font file '%s' vanished", extFontFile->getCString());
>     return NULL;
>   }
>-  fseek(f, 0, SEEK_END);
>+  if (fseek(f, 0, SEEK_END) != 0) {
>+    error(-1, "Cannot seek to end of file");
>+    return NULL;
>+  }
>   *len = (int)ftell(f);
>-  fseek(f, 0, SEEK_SET);
>+  if (fseek(f, 0, SEEK_SET) != 0) {
>+    error(-1, "Cannot seek to start of file");
>+    return NULL;
>+  }
>   buf = (char *)gmalloc(*len);
>   if ((int)fread(buf, 1, *len, f) != *len) {
>     error(-1, "Error reading external font file '%s'",
>diff --git a/poppler/PDFDoc.cc b/poppler/PDFDoc.cc
>index c0c8f58..00ba925 100644
>--- a/poppler/PDFDoc.cc
>+++ b/poppler/PDFDoc.cc
>@@ -181,6 +181,7 @@ PDFDoc::PDFDoc(BaseStream *strA, GooString *ownerPassword,
> }
> 
> GBool PDFDoc::setup(GooString *ownerPassword, GooString *userPassword) {
>+  if (!str->checkIO()) return false;
>   str->reset();
> 
>   // check footer
>@@ -447,6 +448,7 @@ GBool PDFDoc::saveAs(GooString *name, PDFWriteMode mode) {
>     return gFalse;
>   }
>   outStr = new FileOutStream(f,0);
>+  if (!outStr->checkIO()) return false;
>   res = saveAs(outStr, mode);
>   delete outStr;
>   fclose(f);
>@@ -489,6 +491,7 @@ GBool PDFDoc::saveWithoutChangesAs(GooString *name) {
>   }
>   
>   outStr = new FileOutStream(f,0);
>+  if (!outStr->checkIO()) return false;
>   res = saveWithoutChangesAs(outStr);
>   delete outStr;
> 
>diff --git a/poppler/Stream.cc b/poppler/Stream.cc
>index 3ef7146..a8f7480 100644
>--- a/poppler/Stream.cc
>+++ b/poppler/Stream.cc
>@@ -308,9 +308,16 @@ FileOutStream::~FileOutStream ()
>   close ();
> }
> 
>+bool FileOutStream::checkIO ()
>+{
>+  if (fseek(f, 1, SEEK_SET) == 0 && fseek(f, 0, SEEK_SET) == 0) return true;
>+  error(-1, "Output file not seekable");
>+  return false;
>+}
>+
> void FileOutStream::reset ()
> {
>-  fseek(f, start, SEEK_SET);
>+  fseek(f, start, SEEK_SET); // ignore failure
> }
> 
> void FileOutStream::close ()
>@@ -652,12 +659,19 @@ FileStream::~FileStream() {
>   close();
> }
> 
>+bool FileStream::checkIO() {
>+  if (fseek(f, 1, SEEK_SET) == 0 && fseek(f, 0, SEEK_SET) == 0) return true;
>+  error(-1, "File empty or not seekable");
>+  return false;
>+}
>+
> Stream *FileStream::makeSubStream(Guint startA, GBool limitedA,
> 				  Guint lengthA, Object *dictA) {
>   return new FileStream(f, startA, limitedA, lengthA, dictA);
> }
> 
> void FileStream::reset() {
>+  // Ignore failure of any seek functions.
> #if HAVE_FSEEKO
>   savePos = (Guint)ftello(f);
>   fseeko(f, start, SEEK_SET);
>@@ -674,6 +688,7 @@ void FileStream::reset() {
> }
> 
> void FileStream::close() {
>+  // Ignore failure of any seek functions.
>   if (saved) {
> #if HAVE_FSEEKO
>     fseeko(f, savePos, SEEK_SET);
>@@ -710,6 +725,7 @@ GBool FileStream::fillBuf() {
> void FileStream::setPos(Guint pos, int dir) {
>   Guint size;
> 
>+  // Ignore failure of any seek functions.
>   if (dir >= 0) {
> #if HAVE_FSEEKO
>     fseeko(f, pos, SEEK_SET);
>diff --git a/poppler/Stream.h b/poppler/Stream.h
>index 74152fc..3a99fa8 100644
>--- a/poppler/Stream.h
>+++ b/poppler/Stream.h
>@@ -177,6 +177,9 @@ public:
>   // Printf-like function                         2,3 because the first arg is class instance ?
>   virtual void printf (const char *format, ...) = 0 ; //__attribute__((format(printf, 2,3))) = 0;
> 
>+  // Similar to Stream::checkIO(), this makes sure fseek() etc. will work.
>+  virtual bool checkIO() = 0;
>+
> private:
>   int ref; // reference count
>     
>@@ -191,6 +194,8 @@ public:
> 
>   virtual ~FileOutStream ();
> 
>+  virtual bool checkIO();
>+
>   virtual void reset();
> 
>   virtual void close();
>@@ -231,6 +236,16 @@ public:
>   virtual Guint getStart() = 0;
>   virtual void moveStart(int delta) = 0;
> 
>+  // Check that any necessary I/O for this stream is working.
>+  // In particular, for file streams this happens to check
>+  // that fseek() works.  Call this after constructing the
>+  // stream.
>+  //
>+  // If something is wrong so the stream is unlikely to work,
>+  // this function logs a message and returns false.
>+  //
>+  virtual bool checkIO() = 0;
>+
> private:
> 
>   Object dict;
>@@ -350,6 +365,7 @@ public:
>   FileStream(FILE *fA, Guint startA, GBool limitedA,
> 	     Guint lengthA, Object *dictA);
>   virtual ~FileStream();
>+  virtual bool checkIO();
>   virtual Stream *makeSubStream(Guint startA, GBool limitedA,
> 				Guint lengthA, Object *dictA);
>   virtual StreamKind getKind() { return strFile; }
>@@ -392,6 +408,7 @@ public:
> 
>   MemStream(char *bufA, Guint startA, Guint lengthA, Object *dictA);
>   virtual ~MemStream();
>+  virtual bool checkIO() { return true; }
>   virtual Stream *makeSubStream(Guint start, GBool limited,
> 				Guint lengthA, Object *dictA);
>   virtual StreamKind getKind() { return strWeird; }
>@@ -438,6 +455,7 @@ public:
> 
>   EmbedStream(Stream *strA, Object *dictA, GBool limitedA, Guint lengthA);
>   virtual ~EmbedStream();
>+  virtual bool checkIO() { return true; }
>   virtual Stream *makeSubStream(Guint start, GBool limitedA,
> 				Guint lengthA, Object *dictA);
>   virtual StreamKind getKind() { return str->getKind(); }
>diff --git a/utils/pdfinfo.cc b/utils/pdfinfo.cc
>index 5dbd724..ab9a6f0 100644
>--- a/utils/pdfinfo.cc
>+++ b/utils/pdfinfo.cc
>@@ -135,7 +135,10 @@ int main(int argc, char *argv[]) {
>       Object obj;
> 
>       obj.initNull();
>-      doc = new PDFDoc(new FileStream(stdin, 0, gFalse, 0, &obj), ownerPW, userPW);
>+
>+      FileStream *stream = new FileStream(stdin, 0, gFalse, 0, &obj);
>+      if (!stream->checkIO()) exit(1);
>+      doc = new PDFDoc(stream, ownerPW, userPW);
>   }
> 
>   if (userPW) {
>@@ -258,14 +261,14 @@ int main(int argc, char *argv[]) {
> #endif
>   if (f) {
> #if HAVE_FSEEKO
>-    fseeko(f, 0, SEEK_END);
>-    printf("File size:      %u bytes\n", (Guint)ftello(f));
>+    if (fseeko(f, 0, SEEK_END) == 0)
>+      printf("File size:      %u bytes\n", (Guint)ftello(f));
> #elif HAVE_FSEEK64
>-    fseek64(f, 0, SEEK_END);
>-    printf("File size:      %u bytes\n", (Guint)ftell64(f));
>+    if (fseek64(f, 0, SEEK_END) == 0)
>+      printf("File size:      %u bytes\n", (Guint)ftell64(f));
> #else
>-    fseek(f, 0, SEEK_END);
>-    printf("File size:      %d bytes\n", (int)ftell(f));
>+    if (fseek(f, 0, SEEK_END) == 0)
>+      printf("File size:      %d bytes\n", (int)ftell(f));
> #endif
>     fclose(f);
>   }
>diff --git a/utils/pdftoppm.cc b/utils/pdftoppm.cc
>index 164679d..f61502f 100644
>--- a/utils/pdftoppm.cc
>+++ b/utils/pdftoppm.cc
>@@ -190,7 +190,10 @@ int main(int argc, char *argv[]) {
>       Object obj;
> 
>       obj.initNull();
>-      doc = new PDFDoc(new FileStream(stdin, 0, gFalse, 0, &obj), ownerPW, userPW);
>+
>+      FileStream *stream = new FileStream(stdin, 0, gFalse, 0, &obj);
>+      if (!stream->checkIO()) exit(1);
>+      doc = new PDFDoc(stream, ownerPW, userPW);
>   }
>   if (userPW) {
>     delete userPW;
>diff --git a/utils/pdftotext.cc b/utils/pdftotext.cc
>index a0caed8..c7b0a14 100644
>--- a/utils/pdftotext.cc
>+++ b/utils/pdftotext.cc
>@@ -154,7 +154,10 @@ int main(int argc, char *argv[]) {
>       Object obj;
> 
>       obj.initNull();
>-      doc = new PDFDoc(new FileStream(stdin, 0, gFalse, 0, &obj), ownerPW, userPW);
>+
>+      FileStream *stream = new FileStream(stdin, 0, gFalse, 0, &obj);
>+      if (!stream->checkIO()) exit(1);
>+      doc = new PDFDoc(stream, ownerPW, userPW);
>   }
> 
>   if (userPW) {

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Attachments on bug 14126: 13775 | 15382

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